Biomedical subjects

D Hatsukami

Publications and source records attributed to D Hatsukami.

58 records · Page 4Linked to original sources

PubMedDate not supplied

Effects of high intravenous doses of dynorphin A(1-13) on tail flick latency and central nervous system histology in rats.

Dynorphin A(1-13) blocks opiate withdrawal in rats without producing dependence, and enhances analgesia in morphine-tolerant animals. Its potential use in humans is therefore of interest. Dynorphin A(1-13) has little toxicity when administered at modest doses IV but has been reported to cause hindlimb paralysis and necrosis of the spinal cord in rats, at the catheter tip, when administered intrathecally. To further evaluate its potential neurotoxicity, we administered dynorphin A(1-13) to rats at very high doses IV. Rats (n = 6-10 per group) received dynorphin A(1-13) as bolus IV doses of 5 mg/kg, or as continuous IV infusions of 40 mg/kg/day for 1 day, with saline controls. The appearance and behavior of all animals was normal. Tail flick latencies remained unchanged (p > 0.5). There were no histologic abnormalities of the spinal cord or brain when examined by light microscopy. Two additional groups received bolus injections of dynorphin A(1-13) 50 or 100 mg/kg IV. Animals receiving 50 mg/kg showed cutaneous flushing, labored respirations, and decreased spontaneous movement, which resolved within 10 min. Histology at 1 week was normal. All six animals receiving 100 mg/kg convulsed and died within minutes. Three animals that received dynorphin A(1-13) 40 mg/kg/day for 7 days had normal behavior and histology. We conclude that the previously observed neurotoxicity of intrathecally administered dynorphin A(1-13) is a local effect that does not occur when dynorphin A(1-13) is administered IV, even at very high doses.

Analgesics, Opioid↗

PubMedDate not supplied

Smoking topography in tobacco chippers and dependent smokers.

Although most cigarette smokers exhibit signs of tobacco dependence, a subset of this population, referred to as tobacco chippers, does not show characteristic signs of dependence. Few studies have attempted to characterize differences between these groups of smokers. The purpose of the present study was to examine smoking topography in chippers (CH) and dependent smokers (DS). Topographical variables including puff number and duration, and intercigarette interval were examined in seven CH and seven DS under both laboratory and naturalistic conditions. Saliva nicotine, cotinine, and thiocyanate, as well as expired air carbon monoxide (CO) levels were also measured. The results indicate that there were no differences in smoking topography between CH and DS, except those that would be expected based on selection criteria. Although there were differences between groups on pre- and postsmoking CO and saliva cotinine levels, there were no differences in change scores from pre- to postsmoking on these measures. Additional studies will need to be done in order to completely characterize differences between CH and DS.

Adult↗

PubMedDate not supplied

Energy intake and energy expenditure during the menstrual cycle in short-term smoking cessation.

The effect of short-term smoking abstinence on energy intake and expenditure parameters was investigated for women in different phases of the menstrual cycle (follicular or late luteal) in a rigorous inpatient laboratory setting. Twenty-one participants were randomized to a continued smoking (n = 5) or a smoking abstinence (n = 16) group and admitted for 2 7-day inpatient periods during alternate cycle phases. The smoking abstinence group experienced 2 days of baseline smoking and 5 days of smoking abstinence. Measurements included caloric intake (kcal/24 hours), energy expenditure (by indirect calorimetry), and weight. Results of within-subject analyses indicated no smoking abstinence effect on mean daily total kilocalorie intake, sweet kilocalorie intake, or resting metabolic rate. However, a significant cycle phase effect was observed, with increased kilocalorie intake and expenditure-as well as minor weight gain-occurring during the late luteal phase when premenstrual symptoms are highest. In light of this phase effect, women smokers might benefit by attempting to quit smoking during the follicular phase of their cycle.

Adult↗

PubMedDate not supplied

Minors' access to snuff: purchase outcomes at corporate owned and independently owned convenience stores.

Results from many studies indicated that sales clerks sell cigarettes to minors. However, not many researchers have investigated how frequently merchants sell smokeless tobacco to minors. In the present study, sales of snuff to minors were assessed at corporate owned chains of convenience stores and at independently owned convenience stores. Two corporate owned chains with the largest number of convenience stores were selected (n = 45). A random sample of 45 independently owned convenience stores that held current tobacco licenses were also chosen. Two underage males attempted to purchase moist snuff at each of the 90 convenience stores included in the sample. Overall, underage buyers were sold snuff on one out of four purchase attempts. Sales occurred significantly more often in independently owned stores (35.6%) than in corporate owned stores (13.3%). An important variable that appeared to determine whether the sales clerk sold snuff was request for identification.

Adolescent↗