The effect of in-person primary and secondary school instruction on county-level SARS-CoV-2 spread in Indiana

Objective

To determine the county-level effect of in-person primary and secondary school reopening on daily cases of SARS-CoV-2 in Indiana.

Methods

This is a county-level population-based study using a panel data regression analysis of the proportion of in-person learning to evaluate an association with community-wide daily new SARS-CoV-2 cases. The study period was July 12-October 6, 2020. We included 73 out of 92 (79.3%) Indiana counties in the analysis, accounting for 85.7% of school corporations and 90.6% of student enrollment statewide. The primary exposure was the proportion of students returning to in-person instruction. The primary outcome was the daily new SARS-CoV-2 cases per 100,000 residents at the county level.

Results

There is a statistically significant relationship between the proportion of students attending K-12 schools in-person and the county level daily cases of SARS-CoV-2 28 days later. For all ages, the coefficient of interest (β) is estimated at 3.36 (95% CI: 1.91—4.81; p < 0.001). This coefficient represents the effect of a change the proportion of students attending in-person on new daily cases 28 days later. For example, a 10 percentage point increase in K-12 students attending school in-person is associated with a daily increase in SARS-CoV-2 cases in the county equal to 0.336 cases/100,000 residents of all ages.

Conclusion

In-person primary and secondary school is associated with a statistically significant but proportionally small increase in the spread of SARS-CoV-2 cases.

Elemental bioimaging by means of LA-ICP-OES: investigation of the calcium, sodium and potassium distribution in tobacco plant stems and leaf petioles

Laser ablation-inductively coupled plasma-optical emission spectroscopy (LA-ICP-OES) is presented as a valuable tool for elemental bioimaging of alkali and earth alkali elements in plants. Whereas LA-ICP-OES is commonly used for micro analysis of solid samples, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) has advanced to the gold standard for bioimaging. However, especially for easily excitable and ubiquitous elements such as alkali and earth alkali elements, LA-ICP-OES holds some advantages regarding simultaneous detection, costs, contamination, and user-friendliness. This is demonstrated by determining the calcium, sodium and potassium distribution in tobacco plant stem and leaf petiole tissues. A quantification of the calcium contents in a concentration range up to 1000 μg g-1 using matrix-matched standards is presented as well. The method is directly compared to a LA-ICP-MS approach by analyzing parallel slices of the same samples.

Effect of chenodeoxycholic acid and the bile acid sequestrant colesevelam on glucagon-like peptide-1 secretion

AIM

To evaluate the effects of the primary human bile acid, chenodeoxycholic acid (CDCA), and the bile acid sequestrant (BAS) colesevelam, instilled into the stomach, on plasma levels of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide, glucose, insulin, C-peptide, glucagon, cholecystokinin and gastrin, as well as on gastric emptying, gallbladder volume, appetite and food intake.

METHODS

On four separate days, nine patients with type 2 diabetes, and 10 matched healthy control subjects received bolus instillations of (i) CDCA, (ii) colesevelam, (iii) CDCA + colesevelam or (iv) placebo. At baseline and for 180 min after instillation, blood was sampled.

RESULTS

In both the type 2 diabetes group and the healthy control group, CDCA elicited an increase in GLP-1 levels compared with colesevelam, CDCA + colesevelam and placebo, respectively (p < 0.05). The interventions did not affect plasma glucose, insulin or C-peptide concentrations in any of the groups. CDCA elicited a small increase in plasma insulin : glucose ratio compared with colesevelam, CDCA + colesevelam and placebo in both groups. Compared with colesevelam, CDCA + colesevelam and placebo, respectively, CDCA increased glucagon and delayed gastric emptying in both groups.

CONCLUSIONS

CDCA increased GLP-1 and glucagon secretion, and delayed gastric emptying. We speculate that bile acid-induced activation of TGR5 on L cells increases GLP-1 secretion, which, in turn, may result in amplification of glucose-stimulated insulin secretion. Furthermore our data suggest that colesevelam does not have an acute effect on GLP-1 secretion in humans.

Quantitative imaging of platinum based on laser ablation-inductively coupled plasma-mass spectrometry to investigate toxic side effects of cisplatin

This work presents a quantitative bioimaging method for platinum based on laser ablation-inductively coupled plasma-mass spectrometry and its application for a biomedical study concerning toxic side effects of cisplatin. To trace the histopathology back to cisplatin, platinum was localized and quantified in major functional units of testicle, cochlea, kidney, nerve and brain sections from cisplatin treated mice. The direct consideration of the histology enables precise interpretation of the Pt images and the novel quantitative evaluation approach allows significantly more precise investigations than the pure image. For the first time, platinum was detected and quantified in all major injured structures including organ of Corti of cochlea and seminiferous tubule of testicle. In this way, proximal tubule in kidney, Leydig cells in testicle, stria vascularis and organ of Corti in cochlea and nerve fibers in sciatic nerves are confirmed as targets of cisplatin in these organs. However, the accumulation of platinum in almost all investigated structures also raises questions about more complex pathogenesis including direct and indirect interruption of several biological processes.

Phase 1 dose-escalation study of a siRNA targeting the RTP801 gene in age-related macular degeneration patients

BACKGROUND

To evaluate the safety, tolerability, pharmacokinetics, and dose-limiting toxicities of a single intravitreal (IVT) injection of PF-04523655, a 19-nucleotide, O-methyl stabilized, double-stranded small interfering ribonucleic acid targeting the RTP801 gene in patients with neovascular age-related macular degeneration (AMD).

METHODS

Prospective, phase 1, clinical multicentre trial, enrolled 27 patients with neovascular AMD unresponsive to prior treatment and best corrected visual acuity (BCVA) ≤ 20/200 in the study eye in stratum 1: (dose-escalating, open-label: 50 to 3000 μg of PF-04523655) and 27 patients who had potential to benefit from therapy and BCVA of ≤ 20/100 and ≥ 20/800 in stratum 2 (parallel, masked study of 1000, 1500, 2250, and 3000 μg of PF-04523655). The primary outcome was safety and tolerability assessment as well as pharmacokinetic profiling following a single IVT injection of PF-04523655.

RESULTS

Doses of PF-04523655 ≥ 400 μg were generally detectable in the plasma at 1, 4, and 24 h post-injection. And all doses were below the lowest level of quantification by day 14. A single IVT injection of 50 to 3000 μg of PF-045237655 was generally safe and well tolerated over 24 months. There were no dose-limiting toxicities.

CONCLUSION

A single IVT injection of PF-0523655 ≤ 3000 μg seems safe and well tolerated in eyes with neovascular AMD.

Practice parameter: temporal lobe and localized neocortical resections for epilepsy: report of the Quality Standards Subcommittee of the American Academy of Neurology, in association with the American Epilepsy Society and the American Association of Neurological Surgeons

OBJECTIVES/METHODS

To examine evidence for effectiveness of anteromesial temporal lobe and localized neocortical resections for disabling complex partial seizures by systematic review and analysis of the literature since 1990.

RESULTS

One intention-to-treat Class I randomized, controlled trial of surgery for mesial temporal lobe epilepsy found that 58% of patients randomized to be evaluated for surgical therapy (64% of those who received surgery) were free of disabling seizures and 10 to 15% were unimproved at the end of 1 year, compared with 8% free of disabling seizures in the group randomized to continued medical therapy. There was a significant improvement in quantitative quality-of-life scores and a trend toward better social function at the end of 1 year for patients in the surgical group, no surgical mortality, and infrequent morbidity. Twenty-four Class IV series of temporal lobe resections yielded essentially identical results. There are similar Class IV results for localized neocortical resections; no Class I or II studies are available.

CONCLUSIONS

A single Class I study and 24 Class IV studies indicate that the benefits of anteromesial temporal lobe resection for disabling complex partial seizures is greater than continued treatment with antiepileptic drugs, and the risks are at least comparable. For patients who are compromised by such seizures, referral to an epilepsy surgery center should be strongly considered. Further studies are needed to determine if neocortical seizures benefit from surgery, and whether early surgical intervention should be the treatment of choice for certain surgically remediable epileptic syndromes.

Medical THz imaging: an investigation of histo-pathological samples

We present a THz investigation of histo-pathological samples including the larynx of a pig and a human liver with metastasis. Our measurements show that different types of tissue can be clearly distinguished in THz transmission images, either within a single image or by a comparison of images obtained for different frequency windows. This leads to the problem that images obtained for different frequencies inherently have a different spatial resolution. An image obtained from two such images by a simple mathematical operation may contain artefacts. We discuss measures to deal with this problem. Furthermore, we investigate the possibility of improving the spatial resolution of THz images. Finally, we present a cw THz imaging system based on a photomixer and an external cavity semiconductor laser that allows for simultaneous two-mode operation. The cw system is less expensive and more compact than conventional time-domain imaging systems.

Vagal nerve stimulation: adjustments to reduce painful side effects

Vagal nerve stimulation is an approved adjunctive treatment for medically intractable epilepsy. Although it is generally well tolerated, some patients experience pain, coughing, or hoarseness during stimulation. Lowering the pulse width in these patients alleviates pain and reduces voice alteration without loss of efficacy. This allows more optimal programming of stimulation intensities.

Early versus late antiepileptic drug withdrawal for people with epilepsy in remission

BACKGROUND

Antiepileptic drugs ( AEDs) are used to prevent seizures but are associated with both short and long term adverse effects. When epilepsy is in remission, it may be in the patient's best interest to discontinue medication. However, the optimal timing of AED discontinuation is not known.

OBJECTIVES

To quantify seizure relapse risk after early (less than two seizure free years) versus late (more than two seizure free years) AED withdrawal in adult and pediatric epilepsy patients. To assess which variables modify the risk of seizure recurrence.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group trials register, the Cochrane Controlled trials register (Cochrane Library Issue 4, 2000), MEDLINE (January 1996 to January 2001), EMBASE, Index Medicus, CINAHL, as well as hand-searching of journals.

SELECTION CRITERIA

Randomized controlled trials that evaluate withdrawal of AEDs after varying periods of seizure remission in adult and pediatric epilepsy patients with or without blinding were included. Included studies compared an early versus late AED discontinuation.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality. Relative risks with 95% confidence intervals were calculated for each trial. Summary relative risks and 95% confidence intervals for dichotomous data were calculated using a random effects model. A test of statistical heterogeneity was conducted for each pooled relative risk calculation.

MAIN RESULTS

Seven eligible controlled trials were included in the analysis representing 924 randomized pediatric patients. There were no eligible trials evaluating adult seizure free patients. The pooled relative risk for seizure relapse in early versus late AED withdrawal was 1.32 (95% confidence interval 1.02 to 1.70). On the basis of this estimate, the number needed to harm, that is expose an individual to a higher risk of seizure relapse because of early withdrawal of AED, is 10. Early discontinuation was associated with greater relapse rates in patients with partial seizures[pooled RR = 1.52; 95% confidence interval 0.95 to 2.41] or an abnormal EEG [pooled RR=1.67; 95% confidence interval 0.93 to 3.00].

REVIEWER'S CONCLUSIONS

There is evidence to support waiting for at least two or more seizure free years before discontinuing AEDs in children, particularly if individuals have an abnormal EEG and partial seizures. There is insufficient evidence to establish when to withdraw AEDs in pediatric patients with generalized seizures. There is no evidence to guide the timing of withdrawal of AEDs in adult seizure free patients. Further blinded randomized controlled trials are needed to identify the optimal timing of AED withdrawal and risk factors predictive of relapse.

Ipsilateral and contralateral thalamic hypometabolism as a predictor of outcome after temporal lobectomy for seizures

FDG PET is often used to help localize the seizure focus before surgery in patients with medically refractory temporal lobe epilepsy. However, the ability of certain patterns of metabolic landscape to predict postsurgical seizure outcome has not been well characterized. The purpose of this retrospective study was to determine whether FDG PET abnormalities elsewhere in the brain, in combination with those in the temporal lobes, can be used to predict seizure outcome after surgery.

METHODS

Eighty patients with refractory temporal lobe seizures were imaged with PET after intravenous administration of 115 microCi/kg FDG. Images were interpreted without knowledge of clinical information by an experienced reviewer to determine seizure focus and regional metabolic changes in the brain. Metabolic activity scores were assigned for cortical and subcortical structures using the following criteria: 4 = normal activity, 3 = mildly decreased activity, 2 = moderately decreased activity, 1 = severely decreased activity, and 0 = no activity. A laterality index for each region was calculated using the equation 100 x [right - left]/[1/2 x (right + left)]. Seizure focus localization was based on the laterality of temporal lobe metabolic activity and was compared with that determined by scalp and depth electrodes and MRI results. Comparisons were made between asymmetries in metabolic activity in various brain structures and postoperative seizure frequency. Postoperative outcome was determined on the basis of cessation (complete disappearance of seizures) or continuation of seizure activity, regardless of frequency, compared with the preoperative state.

RESULTS

All 64 patients who were free of seizures postoperatively had either no thalamic asymmetry or reduced metabolism on the side from which the temporal lobe was removed. In contrast, 5 of 16 patients (31%) with postoperative seizures of any frequency had hypometabolism in the thalamus contralateral to that of the removed temporal lobe. All 5 patients with reverse thalamic asymmetry had postoperative seizures. Patients with thalamic hypometabolism ipsilateral to the removed temporal lobe also had an increased risk of postoperative seizures, but this risk was not as high as in patients with the contralateral abnormality. In these patients, the temporal lobe (which appeared hypometabolic on PET) was determined to be the site of the seizure on the basis of information besides that provided by PET before surgery.

CONCLUSION

This study indicated that, in patients with temporal lobe epilepsy, thalamic metabolic asymmetry, particularly in the reverse direction to that of the temporal lobe asymmetry, was associated with a poor postsurgical outcome compared with no or matched asymmetry. This determination may be important in evaluating patients for, and selecting optimal candidates for, surgical intervention.

Vagus nerve stimulation therapy for epilepsy in older adults

The authors assessed the efficacy, safety, and tolerability of vagus nerve stimulation (VNS) for refractory epilepsy in 45 adults 50 years of age and older. They determined seizure frequency, adverse effects, and quality of life. At 3 months, 12 patients had a >50% decrease in seizure frequency; at 1 year, 21 of 31 studied individuals had a >50% seizure decrease. Side effects were mild and transient. Quality of life scores improved significantly with time.

[Orientation aids in biopsy specimens]

Histological findings as regards localizing a lesion suspected to be a tumor and its relation to the margins of a surgical specimen have to be as precise as possible and beyond all doubt. We report on our experience with two technical tools which are especially helpful in excisions of breast tissue: 1) Radiopaque suture material fixed intraoperatively simplifies the correlation of postoperative mammography, X-ray findings with biopsy specimens. 2) AgNO(3), as a solution or in stick form, is faster than ink or other dyes, in marking the margins in small or large surgical specimens because virtually no drying is required.

Application of a macrocycle immobilized silica gel sorbent to flow injection on-line microcolumn preconcentration and separation coupled with flame atomic absorption spectrometry for interference-free determination of trace lead in biological and environmental samples

A simple and highly selective flow injection on-line pre-concentration and separation-flame atomic absorption spectrometric method was developed for routine analysis of trace amounts of lead in biological and environmental samples. The selective preconcentration of lead was achieved in a wide range of sample acidity (0.075 to > or = 3 mol L(-1)HNO3) on a microcolumn (145 microL) packed with a macrocycle immobilized on silica gel. The lead retained on the column was effectively eluted with an EDTA solution (0.03 mol L(-1), pH 10.5). Three kinds of potential interferences, i.e., preconcentration inferences from metal ions with an ionic radius similar to that of Pb(II) due to their competition for the cavity of the macrocyle, elution kinetic interferences from ions which form stable complexes with EDTA due to their competition for EDTA, and interferences in the atomizer from residual matrix, were evaluated and compared in view of the read-out mode of the analyte response (peak area vs peak height), column wash step (with vs without), column capacity (50 vs 145 microL), and column shape (conical vs cylindrical). The results showed that a combination of increase in column capacity, quantitation based on peak area, and use of dilute nitric acid for column wash before elution efficiently avoid the above-mentioned potential interferences. With the use of a 145 microL column the present system tolerated up to 0.1 g L(-1) Ba(II), 1 g L(-1) Sr(II), and at least 10 g L(-1) Fe(III), Cu(II), Ni(II), Zn(II), Cd(II), Al(III), K(I), Na(I), CaII), and Mg(II) in the sample digest. Further improvement of the interference tolerance can be achieved by increasing column capacity if more complicated samples need to be analyzed. At a sample loading rate of 3.9 mL min(-1) with 30-s preconcentration, an enrichment factor of 52, a detection limit (3s) of 5 micrograms L(-1) Pb in the digest and a sampling frequency of 63 h(-1) were obtained. The precision (RSD, n = 11) at the 200 micrograms L(-1) level was 1.9%. The enrichment factor and the detection limit can be further improved by increasing sample loading rate without degradation in the efficiency due to the favorable kinetics and low hydrodynamic impedance of the present system. The analytical results obtained by the proposed method for a number of biological and environmental standard reference materials were in good agreement with the certified and recommended values.

On-line coupling flow injection microcolumn separation and preconcentration to electrothermal atomic absorption spectrometry for determination of (ultra)trace selenite and selenate in water

A flow injection manifold with an air-segmented and air-transported operational sequence for on-line coupling of microcolumn separation and preconcentration to electro-thermal atomic absorption spectrometry (ETAAS) was developed for the determination of (ultra)trace selenite and selenate in water. The determination of selenite was achieved by selective reaction with pyrrolidine dithiocarbamate (PDC), sorption of the resultant Se-PDC compound onto a conical microcolumn (10.2 microL) packed with RP C18 sorbent, elution with ethanol, and detection by ETAAS. The concentration of selenate was obtained as the difference between the concentrations of selenite after and before prereduction of selenate to selenite. With the developed manifold and operation sequence,the dispersion during elution and eluate transport and the eluent volume required for complete elution of the sorbed analyte were minimized. As a result, the sorbed analyte was quantitatively eluted from the column with only 26 microL of ethanol, and all the eluate was automatically introduced into the graphite tube by an air flow without the need of preheating the graphite tube or precise timing. Pretreatment of the graphite tube with iridium as a long-term "permanent" modifier effectively prevented analyte loss arising from the high volatility of the Se-PDC compound and greatly improved the precision, sensitivity, and detection limit. One thermal pretreatment of the graphite tube with injection of 150 microgram of iridium made possible at least 200 repetitive atomization cycles. With a preconcentration time of 180 s and a sample flow rate of 1.4 mL min(-1), an enhancement factor of 112 was achieved in comparison with direct injection of 30 microL of aqueous solution. The detection limit (3s) was 4.5 ng L(-1)Se. The RSD (n = 7) was 3.8% at 20 ng L(-1)Se. The concentrations of selenite and selenate determined in synthetic aqueous mixtures were in good agreement with the expected values. The recoveries for selenite from spiked seawater samples ranged from 98 to 102%. The concentrations of selenite in several seawater reference materials obtained with simple aqueous standard solutions for calibration agreed well with the certified and information values, respectively. In addition, the developed method was successfully applied to the certification of selenite and selenate in water.

Outcome after treatment of high-risk papillary and non-Hürthle-cell follicular thyroid carcinoma

BACKGROUND

Treatment of differentiated thyroid cancer has been studied for many years, but the benefits of extensive initial thyroid surgery and the addition of radioiodine therapy or external radiation therapy remain controversial.

OBJECTIVE

To determine the relations among extent of surgery, radioiodine therapy, and external radiation therapy in the treatment of high-risk papillary and non-Hürthle-cell follicular thyroid carcinoma.

DESIGN

Analysis of data from a multicenter study.

SETTING

14 institutions in the United States and Canada participating in the National Thyroid Cancer Treatment Cooperative Study Registry.

PATIENT

385 patients with high-risk thyroid cancer (303 with papillary carcinoma and 82 with follicular carcinoma).

MEASUREMENTS

Death, disease progression, and disease-free survival.

RESULTS

Total or near-total thyroidectomy was done in 85.3% of patients with papillary carcinoma and 71.3% of patients with follicular cancer. Overall surgical complication rate was 14.3%. Total or near-total thyroidectomy improved overall survival (risk ratio [RR], 0.37 [95% CI, 0.18 to 0.75]) but not cancer-specific mortality, progression, or disease-free survival in patients with papillary cancer. No effect of extent of surgery was seen in patients with follicular thyroid cancer. Postoperative iodine-131 was given to 85.4% of patients with papillary cancer and 79.3% of patients with follicular cancer. In patients with papillary cancer, radioiodine therapy was associated with improvement in cancer-specific mortality (RR, 0.30 [CI, 0.09 to 0.93 by multivariate analysis only]) and progression (RR, 0.30 [CI, 0.13 to 0.72]). When tall-cell variants were excluded, the effect on outcome was not significant. After radioiodine therapy, patients with follicular thyroid cancer had improvement in overall mortality (RR, 0.17 [CI, 0.06 to 0.47]), cancer-specific mortality (RR, 0.12 [CI, 0.04 to 0.42]), progression (RR, 0.21 [CI, 0.08 to 0.56]), and disease-free survival (RR, 0.29 [CI, 0.08 to 1.01]). External radiation therapy to the neck was given to 18.5% of patients and was not associated with improved survival, lack of progression, or disease-free survival.

CONCLUSIONS

This study supports improvement in overall and cancer-specific mortality among patients with papillary and follicular thyroid cancer after postoperative iodine-131 therapy. Radioiodine therapy was also associated with improvement in progression in patients with papillary cancer and improvement in progression and disease-free survival in patients with follicular carcinoma.

A dose response study of hepatitis A vaccine in healthy adults who are > or = 30 years old and weigh > or = 77 kg

The dose response relationship of 25-, 50-, and 100-U doses of an inactivated hepatitis A vaccine was examined in 358-seronegative volunteers in a 2-dose schedule. The 50-U and 100-U groups had statistically significantly higher seroconversion rates than the 25-U group at weeks 2, 4, 8, and 24. Seroconversion was statistically significantly greater for the 100-U compared with the 25- and 50-U doses 2 weeks after the first injection but was not significantly different by 4 weeks after the first injection in the 50- and 100-U dose groups. After 2 injections, all subjects in all groups seroconverted. The vaccine was well tolerated at all dosage levels.

Thyrotropin suppression and disease progression in patients with differentiated thyroid cancer: results from the National Thyroid Cancer Treatment Cooperative Registry

The ideal therapy for differentiated thyroid cancer is uncertain. Although thyroid hormone treatment is pivotal, the degree of thyrotropin (TSH) suppression that is required to prevent recurrences has not been studied in detail. We have examined the relation of TSH suppression to baseline disease characteristics and to the likelihood of disease progression in a cohort of thyroid cancer patients who have been followed in a multicenter thyroid cancer registry that was established in 1986. The present study describes 617 patients with papillary and 66 patients with follicular thyroid cancer followed annually for a median of 4.5 years (range 1-8.6 years). Cancer staging was assessed using a staging scheme developed and validated by the registry. Cancer status was defined as no residual disease; progressive disease at any follow-up time; or death from thyroid cancer. A mean TSH score was calculated for each patient by averaging all available TSH determinations, where 1 = undetectable TSH; 2 = subnormal TSH; 3 = normal TSH; and 4 = elevated TSH. Patients were also grouped by their TSH scores: group 1: mean TSH score 1.0-1.99; group 2: mean TSH score 2.0-2.99; group 3: mean TSH score 3.0-4.0. The degree of TSH suppression did not differ between papillary and follicular thyroid cancer patients. However, TSH suppression was greater in papillary cancer patients who were initially classified as being at higher risk for recurrence. This was not the case for follicular cancer patients, where TSH suppression was similar for all patients. For all stages of papillary cancer, a Cox proportional hazards model showed that disease stage, patient age, and radioiodine therapy all predicted disease progression, but TSH score category did not. However, TSH score category was an independent predictor of disease progression in high risk patients (p = 0.03), but was no longer significant when radioiodine therapy was included in the model (p = 0.09). There were too few patients with follicular cancer for multivariate analysis. These data suggest that physicians use greater degrees of TSH suppression in higher risk papillary cancer patients. Our data do not support the concept that greater degrees of TSH suppression are required to prevent disease progression in low-risk patients, but this possibility remains in high-risk patients. Additional studies with more patients and longer follow-up may provide the answer to this important question.

Prospective multicenter study of thyroiscarcinoma treatment: initial analysis of staging and outcome. National Thyroid Cancer Treatment Cooperative Study Registry Group

BACKGROUND

A novel prognostic staging classification encompassing all forms of thyroid carcinoma was created for the National Thyroid Cancer Treatment Cooperative Study (NTCTCS) Registry, with the goal of prospective validation and comparison with other available staging classifications.

METHODS

Patient information was recorded prospectively from 14 institutions. Clinicopathologic staging was based on patient age at diagnosis, tumor histology, tumor size, intrathyroidal multifocality, extraglandular invasion, metastases, and tumor differentiation.

RESULTS

Between 1987 and 1995, 1607 patients were registered. Approximately 43% of patients were classified as NTCTCS Stage I, 24% Stage II, 24% Stage III, and 9% Stage IV. Patients with follicular carcinoma were more likely to have "high risk" Stage III or IV disease than those with papillary carcinoma. Of 1562 patients for whom censored follow-up was available (median follow-up, 40 months), 78 died of thyroid carcinoma or complications of its treatment. Five-year product-limit patient disease specific survival was 99.8% for Stage I, 100% for Stage II, 91.9% for Stage III, and 48.9% for Stage IV (P < 0.0001). The frequency of remaining disease free also declined significantly with increasing stage (94.3% for Stage I, 93.1%for Stage II, 77.8% for Stage III, and 24.6% for Stage IV). The same patients also were staged applying six previously published classifications as appropriate for their tumor type. The predictive value of the NTCTCS Registry staging classification consistently was among the highest for disease specific mortality and for remaining disease free, regardless of the tumor type.

CONCLUSIONS

The NTCTCS Registry staging classification provides a prospectively validated scheme for predicting short term prognosis for patients with thyroid carcinoma.

Speciation determination of arsenic in urine by high-performance liquid chromatography-hydride generation atomic absorption spectrometry with on-line ultraviolet photooxidation

A coupled system for arsenic speciation determination based on high-performance liquid chromatography (HPLC), on-line UV photooxidation and continuous-flow hydride generation atomic absorption spectrometry (HGAAS) was built from commercially available modules with minor modifications to the electronic interface, the software and the gas-liquid separator. The best results were obtained with strong anion-exchange columns, Hamilton PRP X-100 and Supelcosil SAX 1, and gradient elution with phosphate buffers containing KH2PO4-K2HPO4. The on-line UV photooxidation with alkaline peroxodisulfate, 4% m/v K2S2O8-1 mol l-1 NaOH, in a PTFE knotted reactor for 93 s ensures the transformation of inorganic AsIII, monomethylarsonate, dimethylarsinate, arsenobetaine, arsenocholine, trimethylarsine oxide and tetramethylarsonium ion to arsenate. About 32-36 HPLC-UV-HGAAS runs could be performed within 8 h, with limits of detection between 2 and 6 micrograms l-1 As, depending on the species. The method was applied to the analysis of spot urine samples and certified urine reference materials (CRMs). Upon storage at 4 degrees C, reconstituted CRMs are stable for at least 2 weeks with respect to both their total arsenic content and the individual species distribution.

Measurement of cardiac troponin T is an effective method for predicting complications among emergency department patients with chest pain

STUDY OBJECTIVES

To determine the test performance characteristics of serum cardiac troponin T (cTnT) measurement for diagnosis of acute myocardial infarction (AMI), and to determine the ability of cTnT to stratify emergency department patients with chest pain into high- and low-risk groups for cardiac complications.

METHODS

We conducted a prospective observational cohort study with convenience sampling in a tertiary care, urban ED. The study sample comprised 667 patients presenting to the ED with a complaint of chest pain or other symptoms suggesting acute ischemic coronary syndrome (AICS). Patients were assigned to different blood sampling protocols for cTnT therapy on the basis of their ECG at presentation: nondiagnostic for AMI at 0, 3, 6, 9, 12, and 24 hours after ED presentation; or ECG diagnostic for AMI at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 18, and 24 hours after ED presentation.

RESULTS

Of 667 patients, 34 had AMI diagnosed within 24 hours of ED arrival. Using a .2 microgram/L discrimination level for cTnT, sensitivity for AMI within 24 hours of ED arrival was 97% (95% confidence interval, 91.4% to 99.9%), and specificity was 92% (89.8%-94.1%). When the effects of age, race, sex, and creatine kinase-MB isoenzyme subunit test results were controlled, a patient with cTnT of .2 microgram/L or greater was 3.5 (1.4 to 9.1) times more likely to have a cardiac complication within 60 days of ED arrival than a patient with a cTnT value below .2 microgram/L.

CONCLUSION

Measurement of cTnT will accurately identify myocardial necrosis in patients presenting to the ED with possible AICS. Elevated cTnT values identify patients at increased risk of cardiac complications.

Incidence of spikes and paroxysmal rhythmic events in overnight ambulatory computer-assisted EEGs of normal subjects: a multicenter study

The incidences of spikes and paroxysmal rhythmic events (PREs) in 10-h overnight EEGs of normal adult volunteers (n=135) were studied at 11 sites with a computer-assisted ambulatory EEG monitoring system with automatic spike and PRE detection. Spikes were evident in the overnight EEG of 1 subject (0.7%), and PREs were apparent in the overnight EEG of the same subject (0.7%). The incidences of spikes of 24 other subjects with a history of migraine and/or a family history of epilepsy were 12.5 and 13.3%, respectively. The overnight EEGs of these subjects were significantly more likely to show spikes than the overnight EEGs of subjects without migraine or a family history of epilepsy.

Intralesional fluorouracil/epinephrine injectable gel for treatment of condylomata acuminata. A phase 3 clinical study

BACKGROUND AND DESIGN

A new intralesional sustained-release chemotherapy is under development as a treatment for condylomata acuminata; it is administered as an injectable gel that consists of fluorouracil and epinephrine with a purified bovine collagen as the gellant (fluorouracil/epinephrine gel). In this randomized, double-blind study, we evaluated the safety and efficacy of this intralesional treatment in 401 patients, using 2 active drug formulations (fluorouracil/epinephrine gel and fluorouracil gel alone) and a placebo. Each lesion was injected once a week for up to 6 weeks, and patients were followed up for 3 months.

RESULTS

A total of 359 patients with 1926 condylomata underwent evaluation. For all lesions treated with fluorouracil/epinephrine gel, the complete response (CR) rate was 77%. For all patients treated with fluorouracil/epinephrine gel, the CR rate was 61%. The fluorouracil/epinephrine gel was significantly more effective (P < .002) in treating condylomata than the fluorouracil gel without epinephrine (CR rate, 43%); both were superior to placebo (CR rate, 5%). At 3 months after completion of treatment, recurrence rates in patients with CRs were as follows: fluorouracil/epinephrine gel group, 50%; fluorouracil gel group, 58%. No clinically significant drug-related systemic reactions occurred. Finally, the type and severity of local tissue reactions of patients with a positive pretreatment collagen skin test result (6/401 [1.5%]) were similar to those of patients with a negative collagen skin test result.

CONCLUSION

The fluorouracil/epinephrine injectable gel is a safe and effective treatment for condylomata acuminata.

Serum prolactin in neonates with seizures

We studied serum prolactin (PRL) in 28 newborn infants with acute encephalopathy. Six patients had electrographically confirmed seizures. Twenty-two patients comprised the nonictal group. In the seizure group, PRL was determined at the first onset of the seizure (baseline) and at 15 and 30 min postictal. In the nonseizure group, PRL was determined at the end of the EEG and 15 min later. EEGs were visually analyzed for the presence of seizures and background abnormality (normal or mildly, moderately, or markedly abnormal). Etiologic diagnoses included congenital heart disease (12), hypoxic-ischemic encephalopathy (4), sepsis (4), respiratory distress syndrome (5) meconium aspiration (1), and metabolic disease (2). Serum PRL was significantly higher (p < 0.05) at baseline and 15 min postictally in the patients with seizures than in the nonictal group. However, PRL levels 15 and 30 min postictally were not statistically different from baseline values. Baseline PRL correlated significantly (p < 0.001) with EEG background abnormality in both groups; therefore, patients with the most abnormal EEG backgrounds had higher levels of PRL than those with a relatively normal EEG background. We conclude that newborns with EEG-confirmed seizures, particularly if seizures are not associated with clinical signs, have high baseline serum PRL levels that do not increase significantly in the immediate postictal period. Serum PRL levels correlate with the severity of the brain insult as evaluated by EEG background. Further studies are needed to enhance our understanding of the dynamics of PRL secretion in newborns with seizures and acute encephalopathy.

Renal cell carcinomatous meningitis: pathologic and immunohistochemical features

We report the clinical, radiographic, pathologic, and immunohistochemical features of a patient with widespread meningeal carcinomatosis from renal cell carcinoma. Clear and spindle tumor cell subtypes infiltrated the meninges of the cauda equina, oculomotor nerve, spinal cord, and cerebral hemispheres, forming abortive glandular or tubular aggregates without evidence of parenchymal invasion. Cytokeratin epitopes were labeled immunohistochemically with Cam 5.2 antibodies, but epithelial membrane antigen and neuron-specific enolase were not present.

Predictive estimate of blood dose from external counting data preceding radioiodine therapy for thyroid cancer

Bone marrow depression following 131I therapy for metastatic thyroid cancer can occur in up to one-quarter of all patients so treated. An analysis was made of the 131I whole body (WB) retention and its relationship to activity in blood for 46 patients (45 adult, 1 adolescent in 49 total studies) to define the accuracy of utilizing WB external counting data as a predictor of blood dose in comparison to the more classical method which requires data from sequential blood samples. The mean percentage differences between blood dose estimates based on external WB counting and those calculated by the classical method lie within +/- 10%. The WB methodology provides a useful first-order approximation for hematopoietic dose estimates in adult patients undergoing 131I therapy for thyroid cancer.

The functional relationship between antidromically evoked field responses of the dentate gyrus and mossy fiber reorganization in temporal lobe epileptic patients

Field recordings from the dentate granule cell layer of in vitro brain slices of temporal lobe epileptic patients were evoked by antidromic stimulation. Tissue from the same specimen was stained by the Timm-sulfide method to assess the pattern and degree of mossy fiber reorganization into the supragranular layer. A wide range of physiological responses and Timm staining patterns was present across patients. A significant correlation was observed between the abnormality of antidromic responses, reflected by multiple secondary population spikes, and the degree of Timm staining of the supragranular layer. This relationship lends support to the hypothesis that mossy fiber synapses located in the supragranular layer may have functional implications for granule cell excitability in human epileptic tissue.

Differential determination of chromium(VI) and total chromium in natural waters using flow injection on-line separation and preconcentration electrothermal atomic absorption spectrometry

A rapid, sensitive and selective method for the differential determination of CrIII and CrVI in natural waters is described. Chromium(vi) can be determined directly by flow injection on-line sorbent extraction preconcentration coupled with electrothermal atomic absorption spectrometry using sodium diethyldithiocarbamate as the complexing agent and C18 bonded silica reversed-phase sorbent as the column material. Total Cr can be determined after oxidation of CrIII to CrVI by potassium peroxydisulfate. Chromium(III) can be calculated by difference. The optimum conditions for sorbent extraction of CrVI and oxidation of CrIII to CrVI are evaluated. A 12-fold enhancement in sensitivity compared with direct introduction of 40 microliters samples was achieved after preconcentration for 60 s, giving detection limits of 16 ng l-1 for CrVI and 18 ng l-1 for total Cr (based on 3 sigma). Results obtained for sea-water and river water reference materials were all within the certified range for total Cr with a precision of better than 10% relative standard deviation in the range 100-200 ng l-1. The selectivity of the determination of CrVI was evaluated by analysing spiked reference materials in the presence of CrIII, resulting in quantitative recovery of CrVI.

Comparison of the counterregulatory hormone response to semisynthetic human insulin and purified porcine insulin in normal subjects and patients with type I diabetes mellitus

The counterregulatory hormone responses to semisynthetic human insulin and purified porcine insulin were compared in 20 healthy volunteers (ten men and ten women) and 16 patients (8 men and 8 women) with type I diabetes mellitus (IDDM). In both groups blood glucose fell to similar levels following insulin administration; no difference in counterregulatory hormone response or hypoglycemic awareness was noted when comparing human to porcine insulin. However, when men were compared to women, significant differences were noted in basal glucagon, cortisol, and growth hormone levels, as well as in norepinephrine, prolactin, and cortisol responses to hypoglycemia. These differences could not be attributed to insulin species, different doses of insulin, or degree of hypoglycemia. These findings suggest that hormonal response to and awareness of hypoglycemia are similar in healthy subjects and patients with IDDM following administration of human and porcine insulin and that hormonal responses in men and women should be studied separately to avoid confusion in interpreting results arising from differences in sex.

So-called fibroepithelial polyps of the vagina exhibiting an unusual but uniform antigen profile characterized by expression of desmin and steroid hormone receptors but no muscle-specific actin or macrophage markers

The nature of the atypical, often multinucleated stromal cells proliferating in the so-called fibroepithelial polyps of the vagina (FEPV) is obscure. The authors therefore investigated immunohistochemically four polyps of this type with a panel of monoclonal and polyclonal antibodies, including those directed against intermediate filaments, steroid hormone receptors, and macrophage antigens. The authors found that the atypical stromal cells of FEPV expressed vimentin, desmin, and receptors for estrogen and progesterone but lacked all the other markers studied. The homogenous antigen profile strongly suggests that FEPV form a disease entity whose characteristic cells are special hormone-sensitive stromal cells with a myoid component of differentiation. Morphologically similar stromal cells expressing steroid hormone receptors but lacking desmin were found in myxomatoid subepithelial regions of the vaginal wall and the cervix.

Reactivity of T cells in mycosis fungoides exhibiting marked epidermotropism with the monoclonal antibody HML-1 that defines a membrane molecule on human mucosal lymphocytes

Twenty-eight cases of cutaneous T cell lymphomas of mycosis fungoides type, 8 of which showed a marked epidermotropism, were investigated for their reactivity with the monoclonal antibody HML-1. This reagent selectively recognizes human benign and malignant intestinal T lymphocytes, but not benign or malignant lymph node T cells. In all cases, the majority of nonepithelium-associated T cells present in the corium were HML-1 negative. In the eight cases with marked epidermotropism, the intraepidermal (IED) T cells were HML-1 positive in three cases, and HML-1 negative in the remaining five cases. The HML-1 positive IED T cells tended to be localized preferentially in the basal layers, whereas the HML-1 negative IED T cells were more diffusely distributed throughout all epidermal cell layers or formed intra-epidermal aggregates. These findings provide further evidence that mycosis fungoides is not a single entity, but represents a group of neoplasms originating from different T cell subsets that have in common their tropism to epidermis and/or dermis, and thus have a similar clinical presentation.

Identification of a T cell lymphoma category derived from intestinal-mucosa-associated T cells

2 cases of precursor T cell lymphoma and 37 cases of peripheral T cell lymphoma were investigated for their reactivity with the monoclonal antibody (mAb) HML-1, which recognises human intestinal T lymphocytes but not lymph-node T cells. In all but one of the lymphomas studied, the tumour cells were unreactive with the mAb HML-1. The HML-1+ lymphoma was the only tumour that was primarily localised in the epithelium and lamina propria of the small intestine, and was associated with ulcerative jejunitis and coeliac disease. This result suggests that the HML-1+ lymphoma was derived from intestinal mucosa T lymphocytes and differs from precursor T cell lymphoblastic lymphomas and nodal and cutaneous peripheral T cell lymphomas.

Insulin autoantibodies at diagnosis of insulin-dependent diabetes: effect on the antibody response to insulin treatment

Insulin autoantibodies (IAA) are frequently found in newly diagnosed untreated insulin-dependent diabetics. We evaluated whether the insulin antibody response over the first year of treatment with insulin was different in individuals with IAA v those without IAA. One hundred five previously untreated type I diabetics were randomly assigned to treatment with either pure porcine or mixed bovine/porcine insulin. Twenty-one in each group had detectable IAA at diagnosis. Percent binding rose in all patients after commencing insulin therapy and was significantly greater in those with IAA at diagnosis irrespective of the type of insulin administered. The elevated binding in the IAA positive patients at all time points was equivalent to the binding that could be attributed to the insulin autoantibodies. Two different mechanisms could explain this greater insulin antibody binding during insulin therapy in the IAA positive patients. First, there may be summation of binding due to insulin autoantibodies and binding due to insulin antibodies formed in response to the exogenous insulin. Alternatively, the insulin antibodies formed in response to exogenous insulin could replace the IAA, with those individuals positive for IAA at diagnosis having a proportionately greater antibody response to injected insulin. Irrespective of the mechanism, patients with IAA at diagnosis develop higher insulin antibody measurements when subsequently treated with exogenous insulin.

Hematoporphyrin derivative uptake and photodynamic therapy in pancreatic carcinoma

Little information is currently available concerning the uptake of porphyrins by pancreatic tumors, or the effect of photodynamic therapy (PDT) on pancreatic cancer. In Syrian golden hamsters (n = 33), the organ distribution of 125I-labeled dihematoporphyrin ether (DHE) was studied in a pancreatic cancer model. In the same animal model the effect of PDT was studied using a gold vapor laser for energy delivery 3 hr after the injection of DHE (n = 7). DHE was 2.4 times more concentrated in the pancreatic tumor than in the nontumorous pancreas at 3 hr. Simultaneously there was a considerable accumulation of DHE in the surrounding gastrointestinal tract, causing perforation of the duodenum and jejunum with resultant death in four (57%) animals after PDT. Photodynamic therapy caused extensive tumor necrosis without any obvious effect on the nontumor-bearing pancreas. Damage to the surrounding tissue in the hamster indicates that precautions should be taken if PDT is to be used clinically in pancreatic cancer. Intratumoral injection of DHE may give higher drug concentrations with greater specificity for tumor treatment.