Dopamine agonist therapy for neglect in humans

Lesions of ascending dopaminergic pathways induce neglect in animals. Apomorphine, a dopamine receptor agonist, decreases the magnitude of neglect in rats with cortical lesions. We treated two patients with 15 mg of bromocriptine daily for 3 to 4 weeks, one with chronic (longer than 6 months) and one with relatively more acute disabling neglect. Tests for neglect that significantly improved on therapy and worsened after its withdrawal included line, letter, and geometric figure cancellation tasks. Neither patient noted any untoward effects. Based on this open trial of dopamine agonist therapy in humans with neglect, larger controlled studies may be warranted.     

Randomised controlled trial of ranitidine versus omeprazole in combination with antibiotics for eradication of Helicobacter pylori.

This study compared high dose ranitidine versus low dose omeprazole with antibiotics for the eradication of H pylori. 80 patients (mean age 48 years, range 18-75) who had H pylori infection were randomised in an investigator-blind manner to either a two-week regime of omeprazole 20 mg daily, amoxycillin 500 mg tid and metronidazole 400 mg tid (OAM), or ranitidine 600 mg bd, amoxycillin 500 mg tid and metronidazole 400 mg tid (RAM), or omeprazole 20 mg daily and clarithromycin 500 mg tid (OC), or omeprazole 20 mg daily and placebo (OP). H pylori was eradicated in 6 of 19 patients in the OAM group (32%); 8 of 18 in the RAM group (44%), 4 of 15 in the OC group (27%); none of 18 in the OP group (0%). [< P0.005 for OAM, RAM, OC vs OP; P = N.S. between OAM, RAM, OC]. Overall metronidazole resistance was unexpectedly high at 58%. Eradication rates in metronidazole sensitive patients were 71% (5/7) and 100% (3/3) for OAM and RAM respectively. In conclusion, H pylori eradication rates using high dose ranitidine plus amoxycillin and metronidazole may be similar to that of low dose omeprazole in combination with the same antibiotics for omeprazole with clarithromycin. Overall eradication rates were low due to a high incidence of metronidazole resistance but were higher in metronidazole-sensitive patients. Even high dose ranitidine with two antibiotics achieves a relatively low eradication rate. These metronidazole-based regimens cannot be recommended in areas with a high incidence of metronidazole resistance.     

DNA transfection of a gene repressing aryl hydrocarbon hydroxylase induction

High mol. wt genomic DNA from a genetically dominant aryl hydrocarbonhydroxylase (AHH)-deficient mutant cell line derived from themouse hepatoma cell line Hepa-1 was used to transfect the parentcell line. AHH-deficient transfectants were recovered followingsingle-step selection in medium containing the carcinogen benzo(a)pyrene.The transfectants arose at a frequency of 2 x 10^–7. Thisfrequency was at least 4-fold greater than the frequency ofspontaneous forward mutation in this cell line. In another setof experiments, dominant mutant DNA was co-transfected alongwith the selectable plasmid pSV2ecogpt into parental Hepa-1cells. The frequency of co-transfection was determined to be3 x 10^–8. This frequency was 150 times greater than thatexpected on the basis of coincident but unrelated spontaneousmutation and plasmid uptake. Both types of transfectants werejudged, following somatic cell hybridizations, to possess thedominant phenotype of the mutant cell line, demonstrating thata trans-acting dominant negative regulator of AHH was transferredin these experiments. DNA transfection should therefore providea means for the molecular cloning of the gene that encodes thedominant regulator.     

Reducing cancer risk with vitamins C, e, and selenium

Abstract Current research has provided evidence that nearly 90 percent of all cancers may be related to diet, environment, and lifestyle. Of this number, 30 to 40 percent of cancers in men and up to 60 percent of cancers in women may be related to diet and nutrition. The two-stage process in the formation of many cancers, defined as initiation and promotion, is influenced by many dietary components. Vitamins C, E, and the mineral selenium are nutrients that function as antioxidants, reducing potential cancer-causing chemicals in the body. These natural anticarcinogens are thought to alter the cancer process and are currently under study for their cancer prevention properties. The functions, Recommended Dietary Allowances, food sources, research evidence for cancer prevention, and recommendations for supplementation are presented for these three nutrients. Research suggests that the proper and prudent use of nutrients, along with a healthy diet and lifestyle, may offer protection against this devastating disease.     

Right-hand superiority for throwing but not for intercepting

In humans, the organization of movements performed by both upper limbs, relies significantly on a left hemisphere "praxis" system that also subsumes speech function. Right hand preference may also be an expression of this left hemisphere dependence, arising from the preferential connections of the right hand to the left hemisphere. Consequently, a manual task that maximizes the spatial complexity of a target (presumably engaging right hemisphere mechanisms), while concurrently minimizing motor-programming demands, was expected to yield a diminished disparity in preference and performance between the hands. Left and right hand accuracy were measured independently for two motor tasks in 48 normal right-handed university students. In the first task, darts were thrown overhand at a stationary target. For the second task, subjects were asked to use the open hand to block (but not catch) projectiles launched at varying trajectories and velocities. ANOVA yielded a significant Hand x Task interaction, in which the left hand did not differ from the right hand in intercepting ability, but was significantly less accurate than the right hand for throwing. A sex difference favouring males was found for both tasks; this difference was not reducible to differences in physique or athleticism.     

Impact of therapeutic management on use of seclusion and restraint with disruptive adolescent inpatients

Use of seclusion and restraint on three inpatient adolescent psychiatric units was examined during two five-month periods before and after implementation of a "therapeutic management" protocol. Under the protocol, staff classified disruptive behaviors into four stages and provided verbal and behavioral interventions to control behavior at each stage. Patients who required seclusion and restraint had significant latitude to determine the timing of their release from the interventions and met with staff one hour and 24 hours after their release to explore alternatives to aggression. The number of episodes of seclusion and restraint fell by 64 percent after the protocol was adopted, and the number of patients who required those interventions dropped by 39 percent. The mean duration of episodes of seclusion and restraint was reduced by 59 percent. Therapeutic management provides a corrective experience by addressing the developmental needs, deficient cognitive skills, and poor internalized controls of disruptive adolescents.     

The extent of immunological privilege of orthotopic corneal grafts in the inbred rat

Corneal grafts are believed to enjoy a degree of "immunological privilege" primarily due to the avascularity of the recipient bed. In this study orthotopic full-thickness corneal grafts were carried out in the inbred rat, using a technique that is a close model of corneal grafting in humans. The survival times of corneal grafts on nonvascularized beds of 28 fully allogeneic strain combinations were determined without the use of immunosuppression. Some combinations were rejected rapidly, e.g. DA (RT1a) into BN (RT1n) with a mean survival time (MST) +/- SD of 7.8 +/- 1.3 days, and some at a moderate rate, e.g. AO (RT1u) into LEW (RT1l) with an MST of 23.1 +/- 10.0 days, whereas in other cases survival was indefinite, e.g. WAG (RT1u) into PVG (RT1c), an MST of greater than 100 days. Orthotopic corneal grafts on nonvascularized beds between DA and AO parents and the F1, followed the basic rules of transplantation genetics. In addition, the rate of graft rejection was significantly faster (P less than 0.001) with corneal grafts from DA into AO placed onto a vascularized compared with a nonvascularized corneal bed (MST of 6.8 +/- 2.4 or 12.1 +/- 4.0 days respectively). The rate of rejection of corneas on a vascularized bed was at a similar rate to that of orthotopic skin or heterotopic auxiliary heart grafts. The results indicate that the fate of a corneal allograft on a nonvascularized bed is dependent upon the particular combination of donor and recipient strain. No consistent association was observed between any donor or recipient RT1 haplotype and survival; this suggests that non-RT1 background genes may play a role in the survival of corneal grafts.     

Drug use and policy in Poland in the 1980s

In this article, the author describes the recent changes in patterns of drug use in Poland in the light of available data. A much higher incidence of use has been seen in the 1980s, and there are indications that this can be accounted for by increased use among young people from the manual working class. Social deprivation may play a part in the etiology of the 1980s "epidemic," and evidence is put forward in support of this view. Both patterns of use and the policies that have been introduced to deal with them are viewed in terms of the political, economic, and social context of post-Solidarity perestroika.     

Fat embolism associated with cementing of femoral stems designed for press-fit application

The authors report four cases of fat embolism syndrome following total hip arthroplasty using cementless acetabular press-fit components and cemented press-fit femoral components. Factors implicated in the production of this syndrome following "hybrid" total hip arthroplasty include increased canal pressure during femoral reaming and prosthetic insertion, retained marrow elements and reaming debris, and the use of lumbar epidural anesthesia. This potentially fatal syndrome must be a recognized complication following the use of cemented press-fit femoral stems. Specific recommendations for decreasing the incidence of this complication are reviewed.