Advances in algal-prokaryotic wastewater treatment: A review of nitrogen transformations, reactor configurations and molecular tools

The synergistic activity of algae and prokaryotic microorganisms can be used to improve the efficiency of biological wastewater treatment, particularly with regards to nitrogen removal. For example, algae can provide oxygen through photosynthesis needed for aerobic degradation of organic carbon and nitrification and harvested algal-prokaryotic biomass can be used to produce high value chemicals or biogas. Algal-prokaryotic consortia have been used to treat wastewater in different types of reactors, including waste stabilization ponds, high rate algal ponds and closed photobioreactors. This review addresses the current literature and identifies research gaps related to the following topics: 1) the complex interactions between algae and prokaryotes in wastewater treatment; 2) advances in bioreactor technologies that can achieve high nitrogen removal efficiencies in small reactor volumes, such as algal-prokaryotic biofilm reactors and enhanced algal-prokaryotic treatment systems (EAPS); 3) molecular tools that have expanded our understanding of the activities of algal and prokaryotic communities in wastewater treatment processes.

Somatoform symptoms and treatment nonadherence in depressed family medicine outpatients

OBJECTIVES

To examine whether somatoform symptoms, specifically symptoms of conversion, somatization, and hypochondriasis, are associated with side-effect reporting and treatment nonadherence in depressed family medicine outpatients, and to measure whether symptoms improve with pharmacotherapy.

DESIGN

Inception cohort study with 14-week follow-up.

SETTING

Inner-city family medicine residency clinic.

PATIENTS

Thirty-nine consecutive adults with major depressive disorder were asked to participate, and 30 consented.

INTERVENTION

Antidepressants for 14 weeks.

MAIN OUTCOME MEASURES

The Personality Assessment Inventory (PAI) was administered before treatment. The PAI is a self-reported inventory compatible with the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, designed to measure a broad range of personality characteristics. After 14 weeks, the side-effect incidence and treatment nonadherence rates were determined, and 12 patients were readministered the PAI.

RESULTS

Depressed family medicine patients demonstrated trends toward elevated Somatic Complaints scale and conversion subscale scores and a lower Suicidal Ideation scale score relative to those of a standardized depressed psychiatric patient profile. Conversion and hypochondriacal symptoms were associated with side-effect reporting and treatment nonadherence. Somatization and hypochondriacal symptoms improved clinically and statistically during treatment for depression.

CONCLUSIONS

Somatoform distress is a complex, common, and understudied phenomenon in primary care that can adversely affect the treatment of depression. Somatoform symptoms of conversion and hypochondriasis, but not somatization, were found to be risk factors for treatment nonadherence. Somatization and hypochondriacal symptoms may represent personality states that improve with pharmacotherapy, and conversion symptoms may be a personality trait resistant to medical treatment for depression.

Peripheral nerve regeneration across 14-mm gaps: a comparison of autograft and entubulation repair methods in the rat

A study was conducted to compare the regeneration across 1.4-cm peroneal nerve gaps in rats, repaired with sutured autografts or with artificial nerve grafts. The artificial models were composed of a biodegradable passive conduit made of glycolide trimethylene carbonate, filled with either phosphate-buffered saline or a collagen extracellular matrix. Functional recovery was evaluated by walking track analysis throughout the experiment. After 9 months, the nerves were analyzed by electrophysiology and by qualitative and quantitative histology. Walking track analysis demonstrated the three repair methods to provide statistically equivalent recovery, except at day 195 post-engraftment, when the collagen-filled conduit was superior to the saline-filled conduit. Electrophysiologically, the autograft was superior to the collagen-filled conduit, while the collagen- and saline-filled conduits were equivalent. Quantitative histology demonstrated that normal intact nerve had larger mean myelinated axonal diameters but an equal number of axons to the three repair methods, and that the repair methods were statistically equivalent. While the repair methods had similar histologic and functional outcomes, combined standardized scoring demonstrated that the autograft was superior to the statistically-equivalent entubulation repairs. A collagen gel may serve as an ideal matrix in which to suspend neurotrop(h)ic factors or cells.