Neonatal polycythemia: is partial exchange transfusion justified?

In clinical practice, neonatal polycythemia has been used as a marker for neonatal hyperviscosity, implicated as a cause of long-term neurologic delay and damage in the growing child. Clinicians have focused on the newborn infant's hematocrit (Hct) level as the criterion for therapeutic intervention. Partial exchange transfusion is traditionally used as the method to lower the Hct and treat hyperviscosity; however, it is unclear whether this is an effective approach in preventing the long-term neurologic consequences. This article re-evaluates this clinical approach to the diagnosis and treatment of neonatal polycythemia and suggests that this controversial therapy needs re-evaluation.     

Thrombophilia and pregnancy complications

OBJECTIVE: This systematic review examines the strength of the association between thrombophilia and recurrent pregnancy loss and other serious obstetric complications.Study design Electronic databases and manual bibliography searches were used to identify studies evaluating the association between thrombophilia and pregnancy loss, preeclampsia, fetal growth retardation, and placental abruption. RESULTS: Thrombophilic disorders are associated with an increased risk of fetal loss in the majority of case control and cohort studies. The risk is increased throughout pregnancy, but may be higher in the second and third trimester. The common pathologic finding of placental infarction suggests unexplained fetal loss may result from uteroplacental insufficiency and thrombosis. Thrombophilic disorders are not consistently associated with preeclampsia, fetal growth retardation, or placental abruption. Preliminary data suggest prophylactic anticoagulation may improve outcome in thrombophilic women with unexplained recurrent fetal loss. CONCLUSION: Women with thrombophilia have an increased risk of pregnancy loss and possibly other serious obstetric complications, although definition of the magnitude of risk will require prospective longitudinal studies. Preliminary data suggesting prophylactic anticoagulation may improve gestational outcome provide a rationale for prospective randomized trials in thrombophilic women with unexplained recurrent fetal loss.     

The aging and diminishing dental faculty

A dire need for additional dental educators is emerging. This article reflects on the heavily skewed age groups of our current dental educators and the lack of sufficient new faculty to undertake the tasks of faculty members. A literature review is presented of previous studies monitoring the current demographics of dental faculty, projected trends, and factors that influence an individual's career choices concerning dental education involvement. Both intrinsic and extrinsic factors are explored to offer potential avenues for interesting, recruiting, and retaining qualified individuals as dental faculty. The goal of this article is to stimulate thought-provoking discussions and/or solutions within academic dentistry in regard to the question: Who will be our dental school faculty in the next decade?     

Postnatal remodeling of the neural components of the epithelial-mesenchymal trophic unit in the proximal airways of infant rhesus monkeys exposed to ozone and allergen

Nerves and neuroendocrine cells located within the airway epithelium are ideally situated to sample a changing airway environment, to transmit that information to the central nervous system, and to promote trophic interactions between epithelial and mesenchymal cellular and acellular components. We tested the hypothesis that the environmental stresses of ozone (O(3)) and house dust mite allergen (HDMA) in atopic infant rhesus monkeys alter the distribution of airway nerves. Midlevel bronchi and bronchioles from 6-month-old infant monkeys that inhaled filtered air (FA), house dust mite allergen HDMA, O(3), or HDMA + O(3) for 11 episodes (5 days each, 0.5 ppm O(3), 8 h/day followed by 9 days recovery) were examined using immunohistochemistry for the presence of Protein gene product 9.5 (PGP 9.5), a nonspecific neural indicator, and calcitonin gene-related peptide (CGRP). Along the axial path between the sixth and the seventh intrapulmonary airway generations, there were small significant (P < 0.05) decrements in the density of epithelial nerves in monkeys exposed to HDMA or O(3), while in monkeys exposed to HDMA + O(3) there was a greater significant (P < 0.05) reduction in epithelial innervation. In animals exposed to O(3) or HDMA + O(3) there was a significant increase in the number of PGP 9.5 positive/CGRP negative cells that were anchored to the basal lamina and emitted projections in primarily the lateral plain and often intertwined with projections and cell bodies of other similar cells. We conclude that repeated cycles of acute injury and repair associated with the episodic pattern of ozone and allergen exposure alter the normal development of neural innervation of the epithelial compartment and the appearance of a new population of undefined PGP 9.5 positive cells within the epithelium.     

Nitroreductase: a prodrug-activating enzyme for cancer gene therapy

1. The prodrug CB1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide) is activated by Escherichia coli nitroreductase (NTR) to a potent DNA-crosslinking agent. 2. Virus-mediated expression of NTR in tumour cells sensitizes them to CB1954 in vitro and in vivo, providing the basis for a strategy of cancer gene therapy. 3. A phase I trial of CB1954 in cancer patients has been completed, documenting the pharmacokinetics and establishing an acceptable dose. Subsequent trials of the replication-defective adenovirus CTL102 in patients with resectable tumours have documented expression of NTR in injected colorectal liver metastases, hepatocellular carcinoma, head and neck cancer and prostate cancer. Trials combining CTL102 and CB1954 are underway. 4. An oncolytic (replication-competent) adenovirus vector allowed increased expression of NTR in vitro and in a mouse tumour model, resulting in a greater reduction in tumour growth when combined with CB1954 treatment. 5. Alternative prodrugs may eventually prove superior to CB1954; a nitroaryl phosphoramide mustard prodrug activated by NTR shows a greater therapeutic index than CB1954 in a human ovarian carcinoma. 6. The crystal structure of NTR provided the basis for site-directed mutagenesis, which has identified a number of mutants with improved kinetics of CB1954 activation. These can provide improved cell sensitization to CB1954. Combinations of these are being tested. 7. The basis for a positive selection for improved NTR variants has been demonstrated.     

The pediatric use of bilevel positive airway pressure therapy for obstructive sleep apnea syndrome: a retrospective review with analysis of respiratory parameters

The purpose of this study was objective documentation of clinical benefits of bilevel positive airway pressure in pediatric patients with obstructive sleep apnea. We performed a retrospective chart review and data collection/analysis in a suburban tertiary care children's hospital. The study consisted of 10 pediatric patients (age range: 3 to 18 years); 3 patients had craniofacial abnormalities, 1 patient had neuromuscular disease, and 6 patients were obese. Eleven-channel polysomnography and support with bilevel positive airway pressure were used. We measured obstructive sleep apnea indices, lowest oxygen saturation rate, and average breath lengths before and after bilevel positive airway pressure use. We found that the apnea index decreased from 19.7 +/- 26.46 to 0.82 +/- 1.01, the lowest oxygen saturation increased from 75.60% +/- 14.93% to 89.50% +/- 5.50%, and breath length increased from 3.22 +/- 0.95 to 3.68 +/- 0.82. Bilevel positive airway pressure may be considered as a treatment modality for pediatric patients with obstructive sleep apnea.     

Cannabis withdrawal in adolescent treatment seekers

A valid cannabis withdrawal syndrome has been demonstrated in controlled studies with adult marijuana abusers, yet few published reports have examined cannabis withdrawal among adolescents. Adolescents presenting for outpatient substance abuse treatment, whose primary substance of abuse was cannabis, completed a questionnaire reporting the presence and severity of withdrawal symptoms during past periods of cannabis abstinence. Nearly two-thirds of the sample indicated that they had experienced four or more symptoms, and over one-third reported four or more symptoms that occurred at a moderate or greater severity. The magnitude of withdrawal severity was positively correlated with current emotional and behavioral symptoms and self-reported problems with cannabis use. These findings are consistent with previous studies, though the prevalence and magnitude of withdrawal symptoms were lower than that observed in a similar study with adult treatment seekers [Budney, A.J., Novy, P., Hughes, J.R., 1999. Marijuana withdrawal among adults seeking treatment for marijuana dependence. Addiction 94, 1311-1322]. Further research is needed to elucidate associations between cannabis withdrawal effects, the initiation of cessation attempts, and relapse.     

What are the correlates of substance abuse treatment counselor salaries?

This article identifies and measures the key correlates of substance abuse treatment (SAT) counselor salaries. The data come from the 2002-2003 wave of the National Treatment Center Study that consists of approximately 1,500 full-time counselors from nationally representative samples of public and private SAT facilities. We used interval regression models to estimate the relationship between annual salary and numerous counselor and organizational characteristics. We found that counselor characteristics associated with annual salary include education, tenure in the SAT field, licensure, race, recovery status, and administrative responsibilities above and beyond duties as a full-time counselor. Organizational characteristics associated with counselor salary include accreditation status, hospital ownership, and the population density of the county where the facility is located. Taken together, these factors explain approximately 50% of the total variation in SAT counselor salaries.     

Intermittent headaches as the presenting sign of subacute angle-closure glaucoma

Subacute angle closure causes intermittent episodes of transiently elevated intraocular pressure. Headache is often the chief complaint, which may lead to misdiagnosis. The authors examined headache characteristics and consequences of delayed diagnosis. Patients presenting with headaches have a substantial delay in diagnosis, contributing to permanent ocular damage and glaucoma. Patients with subacute angle closure misdiagnosed with migraine are older and have shorter-duration headaches than patients with typical migraine.