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L Jennings

Publications and source records attributed to L Jennings.

At least 19 recordsLinked to original sources
PubMed2001

A redox-based mechanism for the contractile and relaxing effects of NO in the guinea-pig gall bladder.

The purpose of this study was to determine the effects of sodium nitroprusside (SNP), 2,2'-(hydroxynitrosohydrazino)bis-ethanamine (DETA/NO) and 3-morpholinosydnonimine (SIN-1), NO donors which yield different NO reactive species (NO+, NO* and peroxynitrite, respectively), as well as exogenous peroxynitrite, on gall bladder contractility. Under resting tone conditions, SNP induced a dose-dependent contraction with a maximal effect (10.3 +/- 0.7 mN, S.E.M.) at 1 mM. Consistent with these findings, SNP caused a concentration-dependent depolarization of gall bladder smooth muscle. The excitatory effects of SNP were dependent on extracellular calcium entry through L-type Ca2+ channels. Furthermore, the contraction and depolarization were sensitive to tyrosine kinase blockade, and an associated increase in tyrosine phosphorylation was detected in Western blot studies. DETA/NO induced dose-dependent relaxing effects. These relaxations were sensitive to the guanylyl cyclase inhibitor 1H-[1,2,4]oxidiazolo[4,3-a]quinoxaline-1-one (ODQ, 2 microM) but they were not altered by treatment with the potassium channel blockers tetraethylammoniun (TEA, 5 mM) and 4-aminopyridine (4-AP, 5 mM). When tested in a reducing environment (created by 2.5 mM 1,4-dithiothreitol, DTT), SNP caused a relaxation of gall bladder muscle strips. Similarly, the SNP-induced contraction was converted to a relaxation, and associated hyperpolarization, when DTT was added during the steady state of an SNP-induced response. SIN-1 (0.1 mM), which has been shown to release peroxynitrite, induced relaxing effects that were enhanced by superoxide dismutase (SOD, 50 U ml(-1)). The relaxations induced by either SIN-1 alone or SIN-1 in the presence of SOD were strengthened by catalase (1000 U ml(-1)) and abolished by ODQ pretreatment. However, exogenous peroxynitrite induced a concentration-dependent contraction, which was dependent on activation of leukotriene (LT) metabolism and extracellular calcium. The peroxynitrite-induced contraction was abolished in the presence of the peroxynitrite scavenger melatonin. These results suggest that SIN-1 behaves as an NO* rather than a peroxynitrite source. We conclude that, depending on the redox state, NO has opposing effects on the motility of the gall bladder, being a relaxing agent when in NO * form and a contracting agent when in NO+ or peroxynitrite redox species form. Knowledge of the contrasting effects of the different redox forms of NO can clarify our understanding of the effects of NO donors on gall bladder and other smooth muscle cell types.

Acetylcholine↗
PubMed2000

Influenza vaccination coverage in Canterbury rest homes.

AIMS: First, to investigate the effect on Canterbury rest home residents of national policy making influenza vaccination free for those aged 65 years and over. Second, to assess rest home staff influenza vaccination coverage. METHODS: A comparison of influenza vaccination coverage in Canterbury rest home residents during 1996 and 1997 was conducted. Subgroups of rest homes were formed in 1997 to minimise the bias introduced through conducting a coverage survey in 1996. Staff vaccination coverage was also assessed in 1997. RESULTS: Influenza vaccination coverage of Canterbury rest home residents was 74% in 1996 and 76% in 1997. Staff vaccination coverage was 21% in 1997. Significantly more staff were vaccinated in rest homes that offered free influenza vaccination to their staff. CONCLUSIONS: The free influenza vaccination policy had no measurable impact on Canterbury rest home residents' vaccination coverage. This may be due to a ceiling effect of previously high coverage. Coverage was low amongst rest home staff. Providing the vaccination free of charge might improve staff coverage.

Aged↗
PubMed2000

Oral oseltamivir in human experimental influenza B infection.

Oseltamivir is the prodrug of Ro64-0802 (GS4071), a potent and selective inhibitor of influenza A and B virus neuraminidases. Three randomized, double-blind, placebo-controlled, parallel-group studies evaluated oral oseltamivir for early treatment (75 or 150 mg twice daily for 5 days) or prevention (75 mg once or twice daily for 7 days) of experimental influenza B virus infection in healthy susceptible adults. Treatment study A (n=60) demonstrated similar trends to treatment study B (n=117), in which 75 mg doses of oseltamivir introduced 24 h after inoculation reduced median area under curve (AUC) virus titre (oseltamivir, 22.7; placebo, 131.1 log10 TCID50 x h/ml; P=0.002) and duration of viral shedding (oseltamivir, 23.9 h; placebo, 95.8 h; P=0.0005). In prevention study C (n=58), oseltamivir did not reduce infection rates (85 versus 84%) but significantly reduced median AUC virus titre (10.0 versus 66.9 log10 TCID50 x h/ml; P=0.03) and duration of viral shedding (36 versus 84 h; P=0.03) compared with placebo. Oseltamivir was well tolerated. No emergence of drug-resistant variants was detected by testing last-day isolates (n=112) in neuraminidase inhibition assays. These results indicate that oseltamivir has significant antiviral activity in experimental human influenza B virus infection when used for prophylaxis or early treatment.

Acetamides↗
PubMed1999

Tramadol or fentanyl analgesia for ambulatory knee arthroscopy.

In a double-blind, randomized, controlled study, 61 patients who received a standardized anaesthetic for day case arthroscopic knee surgery were studied. Group T (n = 31) received tramadol 1.5 mg kg-1, and group F (n = 30) received fentanyl 1.5 micrograms kg-1 at the induction of anaesthesia. All patients also received 20 mL of intra-articular bupivacaine 0.5% at the end of surgery. Assessments were made of pain at rest and on movement, analgesic requirements and side-effects at hourly intervals up to 6 h and by means of a postal questionnaire at 24 h and 48 h post-operatively. Group F had higher pain scores than group T at 4 h only [VAS 3.3 (1.6-5.5) vs. 2.4 (1-4), P = 0.039, respectively; median (interquartile range)]. There were no other significant differences between the groups in terms of pain scores, supplemental analgesic requirements or incidence of side-effects. We conclude that tramadol offers little benefit clinically compared with fentanyl when used at induction of anaesthesia for day case arthroscopic knee surgery. Further studies are indicated in patients with more severe pain to determine the role of tramadol in post-operative analgesia.

Adolescent↗
PubMed1998

Futurespeak.

Explore the source record for details and available documents.

Communication↗
PubMed1997

The Mental Health Act and professional hostage taking.

Compulsory detention of psychiatric patients is seen as a necessary response to a perceived threat, against themselves or against others, and such detention is rationalized as humane, compassionate and benevolent. However, seen from the recipient's perspective such detention and enforced treatment may be viewed as malevolent. This paper is concerned with examining the role of compulsory detention of the mentally abnormal offender in respect of the 1983 Mental Health Act by analysis of the resultant ideas which underpin it. First, in terms of its role as a sanction against transgressors of a particular value system, who are spotlighted by the increased 'surveillance' in our society. Second, the issues of treatability and consent are discussed in relation to the neo-legalism that permeates our social world. In addition, the role of the 1983 Mental Health Act as a means of social control will be examined using the notion of a covert political 'policing' in the form of compulsory detention, resulting from the medico-legal confrontation of power bases which defines the patient as a 'professional hostage'. Quite clearly there is an overlap of themes which creates a difficulty in interpretation. However, with increasing legal facilities for detention and the increasing number of 'conditions' being drawn under the medical umbrella it is important to attempt to review the results of this legislation within those areas identified above and to understand how this may be interpreted for those held against their wishes.

Commitment of Persons with Psychiatric Disorders↗
PubMed1995

Quality of life improvements at one, two, and five years after liver transplantation.

We prospectively studied adult liver transplant (OLTX) recipients to evaluate the effect of OLTX on quality of life (QOL). Over an 8-year period, all adult patients undergoing OLTX at our institution were asked to complete a psychological questionnaire that probed broad facets of QOL. Patients seen for their 1, 2, and 5 or more-year post-OLTX visits were also asked to complete the form. Questions were then grouped by categories broadly highlighting self-image (SI), health perception (HP), ability to function (F), and ability to work (W). Questions ranged from demographic and occupational topics to symptom distress/frequency, activities of daily living, and the impact of health on daily life. Numerical scores were assigned to each question, and added to derive scores on SI, HP, and F. Higher scores reflect better QOL. Employment data (W) were also compared, though not amenable to scoring. A total of 573 forms were completed (210 pretransplant, 150 at 1 year, 131 at 2 years, 79 at 5 years). All posttransplant scores were significantly higher than pretransplant ones (P < or = .0001, ANOVA). Scores at posttransplant time points were not significantly different from each other. Subscores of SI and HP revealed less symptom frequency and distress following OLTX (P < or = .0003) continuing to beyond 5 years. Health limitations on activities decreased both at 1 year post-OLTX and again at 2 years (P < or = .0001) and were sustained to beyond 5 years. Fewer people were working for pay at 1 year post-compared with pre-OLTX, but pre-OLTX levels of employment had been regained by the second year, continuing to increase to beyond 5 years. OLTX leads to improved QOL by the end of the first posttransplant year, sustained through the 5th posttransplant year and beyond. Self-image, functioning ability, and perception of health status were significantly improved. Ill health interference in daily life continues to decrease as OLTX becomes more remote. Employment suffers early after OLTX, but recovers by the second post-OLTX year and continues to increase long-term.

Female↗
PubMed1994

HLA compatibility and liver transplant outcome. Improved patient survival by HLA and cross-matching.

In liver transplantation (LTx), numerous studies have failed to demonstrate an adverse effect of HLA-A,B,DR incompatibility or of donor-specific positive cross-match on survival of the recipients. In this study, we examined the effect of antidonor cytotoxic antibody and HLA compatibility in 800 LTx recipients with CsA-based immunosuppression. Thirty-four of 482 (7%) recipients were transplanted across a positive donor-specific T cell cross-match. Four-year patient and graft survival was 71% and 67%, respectively, in negative cross-match recipients and 53% and 50%, respectively, in positive cross-match recipients (P = 0.0051 and P = 0.023). Neither B cell-positive cross-match nor the presence of panel reactive antibody (PRA) had an adverse impact on the liver allograft outcome. Interestingly, 21/58 (36.2%) patients with PRA > or = 10% had a positive T cell cross-match, whereas only 7/382 (1.8%) patients with PRA < 10% did (P < 0.0001). This indicates the predictive value of PRA cross-match results. B lymphocyte cross-match results also were strongly correlated with the presence of PRA, as 26/57 (45.6%) of the patients with PRA > or = 10% had a positive cross-match, whereas only 22/394 (5.6%) with PRA < 10% did (P < 0.0001). Analysis of HLA compatibility demonstrated a significant impact on patient's survival, comparing only 0-2 vs. 6 HLA-A+B+DR mismatches and 0 vs. 1 vs. 2 HLA-DR mismatches. Four-year patient survival rate for 0 to 2 antigen mismatches was 86%, whereas for 6 antigen mismatches it was 62% (P = 0.025). Overall actuarial 4-year patient survival rate in HLA-DR-mismatched groups (0 vs. 1 vs. 2) was 84%, 73%, and 64%, respectively (P = 0.033). In no mismatched category was graft survival rate significantly different. Sepsis or rejection was the cause of graft loss in 1/10 (10%), 21/75 (28%), and 34/85 (40%) patients with 0, 1, and 2 HLA-DR mismatches, respectively. The difference between patient and graft survival was accounted for by survival after retransplantation, which was lower in patients with more HLA-DR mismatches in primary transplants. The latter group received intensive immunosuppressive therapy during the first month after primary transplantation, as compared with those with fewer HLA-DR mismatches (P = 0.04). The above data suggest that prospective cross-match should be performed in patients with > or = 10% PRA if it is logistically feasible.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1994

A three-dimensional kinematic method for determining the effectiveness of arm segment rotations in producing racquet-head speed.

The contribution that a segment's anatomical rotations make to racquet-head speed depends on both the segment's angular velocity and the instantaneous position of the head of the racquet with respect to the segment's axes of rotation. Any analysis of racquet swing technique that does not consider both of these factors simultaneously is, at best, incomplete. With this in mind, a three-dimensional kinematic method was developed to determine the effectiveness of the anatomical rotations of the upper arm, forearm, and hand in producing racquet-head speed. The method entailed developing a system of vector equations for three-dimensional upper limb rotations that used displacement histories of 10 selected landmarks as input. The required three-dimensional displacement histories were obtained using three cine cameras and the DLT approach. To test the diagnostic capabilities of the method, a tennis serve was selected for analysis. For the player and serve analyzed, the greatest contribution to racquet-head speed at impact was produced by internal rotation of the upper arm (8 m s-1). Forearm pronation, although exhibiting the fastest rotation at impact (24 rad s-1), ranked only fourth in terms of its contribution (4 m s-1) to racquet-head speed. To test the performance of the method, a comparison was made between the racquet-head speed measured directly from film and the racquet-head speed computed by summing all of the individual segment contributions to speed commencing at the start of forward swing and ending at ball contact. The results indicate that the method can successfully determine the individual contributions that the different anatomical rotational velocities of the arm segments make to the measured instantaneous racquet-head speed.

Algorithms↗
PubMed1993

The impact of operative bleeding on outcome in transplantation of the liver.

Excessive operative blood transfusion has been correlated with an increased rate of infectious complications and lower survival rate after transplantation of the liver. Two hundred and five consecutive transplants of the liver, performed between January 1988 and December 1989, were studied retrospectively to determine preoperative risk factors associated with an increased operative blood loss and to evaluate the impact of operative transfusion on the outcome of transplantation. Preoperative clinical and laboratory parameters in patients who required 10 units or more of banked erythrocytes were compared with those in patients who received less than ten units of erythrocytes. In evaluating the outcome, the two groups were compared for infection, rejection and graft and patient survival rates. The median operative blood loss for 205 patients was 5 units of banked erythrocytes (range of zero to 52, mean of 6.9 units). Only 41 patients (20 percent) required 10 units or more of erythrocytes. The significant factors on univariate analysis that were associated with an increased operative blood loss were hospitalized patients (United Network for Organ Sharing Status > or = 3), fulminant hepatic failure, previous portosystemic shunt and complete ABO mismatch. Patients who required more blood had higher incidence of coagulation abnormalities, renal dysfunction and high bilirubin levels. A stepwise logistic regression analysis model using all these parameters identified an elevated serum creatinine, decreased platelets and a prolonged partial thromboplastin time as being the strongest risk factors. Using these variables, operative bleeding of more than 10 units could be predicted accurately only 60 percent of the time (sensitivity 60.0 percent with a specificity of 69.1 percent). Septic episodes occurred more frequently in patients with an excessive operative blood loss (p < 0.05), and these patients also tended to have a higher rate of severe cytomegalovirus infections and a lower incidence of acute rejection. Patients who required more blood also had significantly prolonged stays in the intensive care units postoperatively (18.3 versus 6.3 days, p < 0.002) and lower graft and patient survival rates (p < 0.001 and p < 0.05, respectively). We conclude that intraoperative bleeding has remained a significant problem affecting the immediate outcome after transplantation of the liver. Preoperative parameters cannot predict operative bleeding accurately and the mainstay to prevent bleeding is a meticulous surgical technique during the hepatectomy and correction of coagulation abnormalities throughout the procedure.

Adult↗
PubMed1990

Hypofrontality and cognitive impairment in schizophrenia: dynamic single-photon tomography and neuropsychological assessment of schizophrenic brain function.

Regional cerebral blood flow (rCBF) was assessed in 40 chronic male schizophrenic patients (20 medicated, 20 unmedicated) and 31 matched normal controls with Dynamic Single-photon Emission Computed Tomography (D-SPECT). Blind analyses of normalized color-coded tomograms revealed significant bifrontal and bitemporal rCBF deficits in the patient group. Frontal flow deficits were most prominent in paranoid patients (n = 21) and right temporal deficits were most prominent in nonparanoid patients (n = 19). These relative regional declines were observed within the context of significantly elevated hemispheric blood flow in schizophrenics compared with controls. Reduced left frontal rCBF was associated with neuropsychological impairment on the Wisconsin Card Sorting Test and Luria-Nebraska Battery. Increased hemispheric CBF was correlated with the presence of positive schizophrenic symptoms. Medication status was unrelated to rCBF. These findings demonstrate that hypofrontality has important implications for cognitive function in some schizophrenic individuals.

Adult↗
PubMed1988

Reduction in the rate of early restenosis after coronary angioplasty by a diet supplemented with n-3 fatty acids.

To determine the safety and benefit of n-3 fatty acid therapy in the prevention of early restenosis after coronary angioplasty, we conducted a randomized, unblinded study comparing a conventional antiplatelet regimen (325 mg of aspirin and 225 mg of dipyridamole per day; control group) with a similar regimen supplemented with 3.2 g of eicosapentaenoic acid per day (treatment group). Treatment began seven days before angioplasty and continued for six months afterward. All angiographic analyses were blinded and performed by a method that was validated by comparison with quantitative coronary angiography. In 82 male patients, 103 coronary lesions were dilated. Both groups had similar base-line clinical and angiographic characteristics. The incidence of early vessel restenosis, as determined on a second angiogram three to four months after angioplasty, was 36 percent in the control group and 16 percent in the treatment group (P = 0.026). The incidence of restenosis per patient was also significantly lower in the treatment group (46 vs. 19 percent). Both multiple logistic regression and Mantel-Haenszel statistical analyses demonstrated a significant independent benefit of treatment with n-3 fatty acids. No important bleeding complications developed in the treated patients. These results, in a male population at relatively high risk for restenosis, suggest that a dietary supplement of n-3 fatty acids, administered for one week before and for six months after coronary angioplasty, is safe and reduces the occurrence of early restenosis after that procedure. Whether this beneficial effect also applies to other populations is unknown.

Angioplasty, Balloon↗
PubMed1988

Painful heel syndrome: radiographic and treatment assessment.

From July 1980 to January 1986, 170 patients who had unilateral heel pain were examined, x-ray filmed, and treated in a similar fashion. Radiographs of painful and nonpainful heels were measured. There was a statistically significant increased thickness of the heel fat pad and subfascial area compared with that of the control subject (the nonpainful side). A tightness of the Achilles tendon and a new sign, which the authors are designating as the "saddle" sign, were other prominent features. A treatment program of stretching exercises and walking seemed to be effective in relief of symptoms.

Heel↗
PubMed1981

Experimental anti-alveolar basement membrane antibody-mediated pneumonitis. I. The role of increased permeability of the alveolar capillary wall induced by oxygen.

Attempts to produce in animals lung lesions mediated by anti-alveolar basement membrane (ABM) antibodies have thus far been inconclusive. The aim of the present study was to test the hypothesis that increased permeability of the endothelial cell lining is needed before circulating antibodies can gain access and bind to ABM. A goat antiserum was prepared against purified rabbit ABM. After i.v. injection of the gamma-globulin fraction into rabbits, goat IgG was detected in glomerular basement membrane but not in ABM. However, 17 of 19 rabbits injected with anti-ABM antibody after exposure for 62 to 66 hr to 100% oxygen had a diffuse linear binding of goat IgG in ABM and died with pulmonary edema and hemorrhagic pneumonitis. By the paired label isotope technique, uptake of anti-ABM antibodies in lung far exceeded that in kidney. Semiquantitative histologic studies indicated that the lesions in the lung of these rabbits were more severe then those found in rabbits exposed to 100% oxygen and injected with normal goat serum gamma-globulin. None of the latter animals died with pulmonary edema; none was found to have binding of goat IgG in the lung. The results indicate that under normal physiologic conditions the endothelium is a barrier that prevents binding of IgG antibodies to ABM. The increased permeability induced by oxygen in the alveolar capillary wall is a nonimmunologic factor allowing the development of a reproducible model of severe anti-ABM antibody-mediated pneumonitis.

Animals↗