Combined Effect of Low-Frequency Ultrasound and Iontophoresis: Applications for Transdermal Heparin Delivery

Pharmaceutical Research -     

GABAergic synaptic interactions in the substantia nigra

The substantia nigra receives a strong GABAergic input from the ipsilateral striatum and globus pallidus. Nigral GABAergic synaptic interactions have been described in the pars compacta (SNC) and pars reticulata (SNR) but not in the pars lateralis (SNL). The SNR and particularly the SNL are the nodal points of the GABAergic nigrotectal pathway. The present study analyzes the synaptic connections of GABAergic and dopaminergic neurons in each of the divisions of the substantia nigra by employing a double-labeling immunocytochemical technique at the light and electron microscope levels. Glutamic acid decar☐ylase (GAD)-containing terminals make symmetrical synaptic contacts with dopaminergic neurons in the SNC and SNR. Neurons that contain GAD also receive a GABAergic input in the SNR and SNL. The proportion of GAD-GAD contacts appears to be highest in the SNL where virtually all GAD-positive terminals are found to be in synaptic contact with or apposed to GAD positive profiles. This study demonstrates a strong GABAergic input onto nigral dopaminergic neurons and GABAergic neurons in the SNR and SNL. This GABAergic influence which is ontensibly striatal or pallidal in origin is particularly prominent in relation to the SNL-mediated nigro-collicular pathway.     

High prevalence of obstructive sleep apnea among patients with head and neck cancer

OBJECTIVES: To determine the prevalence of obstructive sleep apnea (OSA) in patients with cancer of the oral cavity and oropharynx scheduled for primary surgical resection. To correlate the presence of OSA and the occurrence of postoperative morbidities in this patient population. METHODS: This was a prospective study involving 17 patients with malignancies of the oral cavity and oropharynx scheduled for primary surgical resection. Consecutive patients were approached to undergo overnight polysomnography to determine the apnea-hypopnea index (AHI). OSA was defined by an AHI value > or = 20 events per hour. Postoperative morbidities were evaluated in a blinded fashion for the patients completing surgery. RESULTS: OSA was present in 13 of 17 patients, yielding a striking prevalence of 76% in this patient group. The mean AHI for patients with OSA was 44.7 +/- 3.5 (standard error) events per hour, with a mean nadir oxygen saturation of 88.2 +/- 1.8%, consistent with moderate to severe sleep-disordered breathing. The OSA and non-OSA patients were similar with respect to age and body mass index. The mean size of the primary tumour was 3.3 cm in patients with an AHI < 20 and 3.5 cm in those with an AHI > or = 20 (p = not significant). Overall, postoperative complications, defined as prolonged intensive care unit stay (> 24 hours), need for mechanical ventilation, and cardiopulmonary morbidities, were observed in 67% of OSA and 25% of non-OSA patients. CONCLUSIONS: These findings point to a strong association between OSA and malignancies of the oral cavity and oropharynx. This relationship was independent of the size of the primary malignancy in this patient population with tumours ranging from 1 to 7 cm (p = not significant). When comparing the two groups (AHI < 20 and AHI > or = 20), there was a tendency for the group with OSA to have an increase in postoperative morbidities. Further research is warranted to further evaluate the postoperative morbidities and mortalities associated with OSA in this patient population and to determine the potential roles for preoperative treatment with continuous positive airway pressure and tracheotomy.     

Detection of natural anti-angiotensin converting enzyme antibodies in human serum using immunoenzyme technique

Solid-phase enzyme immunoassay (EIA) was developed for detecting natural antibodies to angiotensine-converting enzyme (ACE). Optimal conditions for detecting natural anti-ACE by EIA in the sera of donors and patients with disorders of arterial pressure are selected. The findings indicate that the level of natural anti-ACE is normally constant, while in the patients it is increased in 50% cases.     

Calcium Responsive Bioerodible Drug Delivery System

Pharmaceutical Research -