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J P Higgins

Publications and source records attributed to J P Higgins.

At least 37 records · Page 2Linked to original sources
PubMed2001

Dynamics of the 1 3 pi g state of K2 on helium nanodroplets.

Fluorescence following optical excitation of the 1 3 sigma u+ state of K2 prepared on helium nanodroplets to the predissociative 1 3 pi g state yields molecular emission from both the (B)1 1 pi u and (A)1 1 sigma u+ K2 states as well as atomic emission from the expected 4 2P3/2, 1/2-->4 2S1/2 dissociation channel. A approximately 12 cm-1 red shift is observed in the molecular emission excitation spectrum compared to the atomic emission excitation spectrum. Time-correlated photon counting measurements demonstrate the rise time for both atomic and molecular products to be < 80 ps, independent of vibrational level excited. This lifetime is interpreted as the total depopulation time for the optically excited 1 3 pi g state, which is dominated by intersystem crossing at low vibrational energy and by predissociation at the highest vibrational level. It is deduced that the timescale for intersystem crossing must be of the order of 10 ps. Symmetry restrictions for the isolated K2 imply that the intersystem crossing from the 1 3 pi g state to the (B)1 1 pi u and (A)1 1 sigma u+ states must be induced by interaction with the helium nanodroplet.

Journal Article↗
PubMed2001

Hypothenar hammer syndrome after radial forearm flap harvest: a case report.

A case of acute hypothenar hammer syndrome (HHS) in a high-risk laborer in whom the radial artery had been surgically removed during a prior radial forearm flap harvest is reported. Studies estimating the true incidence of HHS among laborers are reviewed to define the risk of this complication. Two major risk factors must be considered in the assessment of a patient for radial forearm flap harvest. First, the risk for immediate vascular compromise is determined by using a standard Allen's test to assess ulnar artery contribution to hand perfusion. Second, the risk for future vascular compromise is determined. When patients at high risk for HHS are recognized the surgeon should consider other reconstructive alternatives. If the superficial palmar arch is patent and complete and a radial forearm flap is performed, postoperative activity modification and risk counseling should be provided.

Fingers↗
PubMed2000

Interventions for treating hallux valgus (abductovalgus) and bunions.

BACKGROUND: Hallux valgus is classified as an abnormal deviation of the great toe (hallux) towards the midline of the foot. OBJECTIVES: To identify and evaluate the evidence from randomised trials of interventions used to correct hallux valgus. SEARCH STRATEGY: Medline (1966-October 1998), Embase (1980-1998), Cinahl (1982-1998), Amed (1993-1998), the Cochrane Controlled Trials Register, the Cochrane Musculoskeletal Injuries Trials Register and bibliographies of identified trials were searched. Hand searching of podiatry journals was undertaken. Date of the most recent search: October 1998. SELECTION CRITERIA: Randomised or quasi-randomised trials of both conservative and surgical treatments of hallux valgus. Excluded were studies comparing areas of surgery not specific to the control of the deformity such as use of anaesthetics or tourniquet placement. DATA COLLECTION AND ANALYSIS: Methodological quality of trials which met the inclusion criteria was independently assessed by two reviewers. Data extraction was undertaken by one reviewer and confirmed by another. The trials were grouped according to the interventions being compared, but the dissimilarity in the comparisons prevented pooling of results. MAIN RESULTS: The methodological quality of the 12 included trials was poor and trial sizes were small. Two trials involving 150 patients evaluated conservative treatments. There was no difference in outcomes between treatment and no treatment. Two trials involving 133 patients compared Keller's arthroplasty with other surgical techniques. In general, there was no advantage in using Keller's over the other techniques, particularly in terms of range of motion and intermetatarsal angle. Three trials involving 205 patients compared chevron (and chevron-type) osteotomy with other techniques. The chevron osteotomy offered no advantages in these trials. For some outcomes, other techniques gave better results. Three trials involving 157 patients compared outcomes between original operations and surgeon's adaptations. There was no advantage found for any of the adaptations. Two trials involving 95 patients evaluated methods of post-operative rehabilitation. The use of continuous passive motion appeared to give an improved range of motion and earlier recovery following surgery; early weightbearing was not found to be detrimental to final outcome. REVIEWER'S CONCLUSIONS: There is insufficient evidence from randomised trials to determine which methods of either conservative, operative or post-operative treatment are the most appropriate for the hallux valgus. It is notable that the numbers of patients remaining dissatisfied at follow-up were consistently high (25 to 33%), even when the hallux valgus angle and pain had improved. Assessment of future research should focus on evaluating basic intervention types in eligible patients with similar degrees of deformity. Future research should include patient-focused outcomes, standardised assessment criteria and longer surveillance periods.

Hallux Valgus↗
PubMed2000

Lecithin for dementia and cognitive impairment.

BACKGROUND: People with Alzheimer's disease have been found to have a relative lack of the enzyme responsible for converting choline into acetylcholine within the brain. Lecithin is a major dietary source of choline, so extra consumption may assist in the production of acetylcholine and reduce some of the symptoms of dementia. OBJECTIVES: To determine the efficacy of lecithin in the treatment of dementia or cognitive impairment. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Impairment Group Register of Clinical Trials has been searched, as have the electronic databases MEDLINE, EMBASE, Psychlit, ISI and Current Contents. Reference lists and relevant books have been examined. SELECTION CRITERIA: All unconfounded, randomised trials comparing lecithin with placebo in a treatment period longer than one day, in patients with dementia of the Alzheimer type, vascular dementia, mixed vascular and Alzheimer's disease, unclassified or other dementia or unclassified cognitive impairment not fulfilling the criteria for dementia are eligible for inclusion. DATA COLLECTION AND ANALYSIS: Data are extracted by two independent reviewers and cross checked. Meta-analyses are performed when more than one trial provide data on a comparable outcome on sufficiently similar patients. Random effects analyses are performed whenever heterogeneity between results appears to be present. Standardised mean difference are used due do the use of different scales and periods of treatment. Odds ratios for dichotomous data are pooled using the Mantel-Haenszel or DerSimonian and Laird methods. MAIN RESULTS: Eleven randomised trials have been identified involving patients with Alzheimer's disease (265 patients) and Parkinsonian dementia (21 patients). No trials reported any clear clinical benefit of lecithin. Few trials contributed data to meta-analyses. The only statistically significant result was in favour of placebo for adverse events, based on one trial, which appears likely to be a spurious result. REVIEWER'S CONCLUSIONS: Evidence from randomised trials does not support the use of lecithin in the treatment of patients with dementia or cognitive impairment. A moderate effect cannot be ruled out, but results from the small trials to date do not indicate priority for a large randomised trial.

Alzheimer Disease↗
PubMed2000

Reduced or modified dietary fat for prevention of cardiovascular disease.

BACKGROUND: Reduction or modification of dietary fat can improve total cholesterol levels, but may also have a variety of effects, both positive and negative, on other cardiovascular risk factors. OBJECTIVES: The aim of this systematic review was to assess the effect of reduction or modification of dietary fats on total and cardiovascular mortality and cardiovascular morbidity over at least 6 months, using all available randomized clinical trials. SEARCH STRATEGY: The Cochrane Library, MEDLINE, EMBASE, CAB Abstracts, CVRCT registry and related Cochrane Groups' trial registers were searched through spring 1998, SIGLE to January 1999. Trials known to experts in the field and biographies were included through May 1999. SELECTION CRITERIA: Trials fulfilled the following criteria: 1) randomized with appropriate control group, 2) intention to reduce or modify fat or cholesterol intake (excluding exclusively omega-3 fat interventions), 3) not multi factorial, 4) healthy adult humans, 5) intervention at least six months, 6) mortality or cardiovascular morbidity data available. Inclusion decisions were duplicated, disagreement resolved by discussion or a third party. DATA COLLECTION AND ANALYSIS: Rate data were extracted by two independent reviewers and meta-analysis performed using random effects methodology. Meta-regression and funnel plots were used. MAIN RESULTS: Twenty seven studies were included (40 intervention arms, 30,901 person-years). There was no significant effect on total mortality (rate ratio 0.98, 95% CI 0.86 to 1.12), a trend towards protection form cardiovascular mortality (rate ratio 0.91, 95% CI 0. 77 to 1.07), and significant protection from cardiovascular events (rate ratio 0.84, 95% CI 0.72 to 0.99). The latter became non-significant on sensitivity analysis. Trials where participants were involved for more than 2 years showed significant reductions in the rate of cardiovascular events and a suggestion of protection from total mortality. The degree of protection from cardiovascular events appeared similar in high and low risk groups, but was statistically significant only in the former. REVIEWER'S CONCLUSIONS: The findings are suggestive of a small but potentially important reduction in cardiovascular risk in trials longer than two years. Lifestyle advice to all those at high risk of cardiovascular disease (especially where statins are unavailable or rationed), and to lower risk population groups, should continue to include permanent reduction of dietary saturated fat and partial replacement by unsaturates.

Cardiovascular Diseases↗
PubMed2000

Factors affecting outcome in free-tissue transfer in the elderly.

Free-tissue transfers have become the preferred surgical technique to treat complex reconstructive defects. Because these procedures typically require longer operative times and recovery periods, the applicability of free-flap reconstruction in the elderly continues to require ongoing review. The authors performed a retrospective analysis of 100 patients aged 65 years and older who underwent free-tissue transfers to determine preoperative and intraoperative predictors of surgical complications, medical complications, and reconstructive failures. The parameters studied included patient demographics, past medical history, American Society of Anesthesiology (ASA) status, site and cause of the defect, the free tissue transferred, operative time, and postoperative complications, including free-flap success or failure. The mean age of the patients was 72 years. A total of 46 patients underwent free-tissue transfer after head and neck ablation, 27 underwent lower extremity reconstruction in the setting of peripheral vascular disease, 10 had lower extremity traumatic wounds, nine had breast reconstructions, four had infected wounds, two had chronic wounds, and two underwent transfer for lower extremity tumor ablation. Two patients had an ASA status of 1, 49 patients had a status of 2, 45 patients had a status of 3, and four had a status of 4. A total of 104 flaps were transferred in these 100 patients. There were 49 radial forearm flaps, 34 rectus abdominis flaps, seven latissimus dorsi flaps, seven fibular osteocutaneous flaps, three omental flaps, three jejunal flaps, and one lateral arm flap. Four patients had planned double free flaps for their reconstruction. Mean operative time was 7.8 hours (range, 3.5 to 16.5 hours). The overall flap success rate was 97 percent, and the overall reconstructive success rate was 92 percent. There were six additional reconstructive failures related to flap loss, all of which occurred more than 1 month after surgery. Patients with a higher ASA designation experienced more medical complications (p = 0.03) but not surgical complications. Increased operative time resulted in more surgical complications (p = 0.019). All eight cases of reconstructive failure occurred in patients undergoing limb salvage surgery in the setting of peripheral vascular disease. Free-tissue transfer in the elderly population demonstrates similar success rates to those of the general population. Age alone should not be considered a contraindication or an independent risk factor for free-tissue transfer. ASA status and length of operative time are significant predictors of postoperative medical and surgical morbidity. The higher rate of reconstructive failure in the elderly peripheral vascular disease population compares favorably with other treatment modalities for this disease process.

Aged↗
PubMed2000

Levonorgestrel-releasing (20 microgram/day) intrauterine systems (Mirena) compared with other methods of reversible contraceptives.

OBJECTIVE: To assess the relative contraceptive effectiveness, tolerability and acceptability of the levonorgestrel-releasing (20 microg per day) intrauterine system (LNG-20) compared with reversible contraceptive methods in women of reproductive age. DESIGN: A systematic review and meta-analysis of randomised controlled trials. IDENTIFICATION: Studies were identified through seven databases, and by contacting investigators and organisations working in the contraceptive field. MAIN OUTCOME MEASURES: Unplanned pregnancy and continuation of contraceptive method. RESULTS: Five of the seven randomised controlled trials which met the inclusion criteria were included in the meta-analyses; four were comparisons of the LNG-20 intrauterine system with nonhormonal intrauterine devices. LNG-20 intrauterine systems were compared with intrauterine devices divided into two categories, those > 250 mm3 (Copper T 380 Ag and Copper T 380A intrauterine devices) and those < or = 250 mm3 (Nova-T, Copper T 220C and Copper 200 intrauterine devices). Pregnancy rates for the LNG-20 intrauterine system users were significantly less likely to become pregnant compared with users of intrauterine devices < or = 250 mm3, and significantly less likely to have an ectopic pregnancy. LNG-20 intrauterine system users were more likely to experience amenorrhoea and device expulsion than women using intrauterine devices > 250 mm3. LNG-20 intrauterine system users were significantly more likely than all the intrauterine device users to discontinue because of hormonal side effects and amenorrhoea. When the LNG-20 intrauterine system was compared with Norplant-2, the LNG-20 users were significantly more likely to experience oligo-amenorrhoea, but significantly less likely to experience prolonged bleeding and spotting. CONCLUSIONS: The effectiveness of the LNG-20 intrauterine system was similar to or better than other contraceptive methods with which it was compared. Amenorrhoea was the main reason for the discontinuation of the LNG-20 intrauterine system, usually unnecessarily, since this end-organ suppression of bleeding is benign, associated with normal oestrogen levels. Women choosing this method should be informed of potential amenorrhoea when having pre-contraceptive counselling and that absent bleeding may be viewed as a positive outcome.

Contraception↗
PubMed2000

Systematic review of controlled trials of interventions to promote smoke alarms.

AIMS: To evaluate the effects of promotion of residential smoke alarms. METHODS: Electronic databases, conference proceedings, and bibliographies were systematically searched, and investigators and organisations were contacted, in order to identify controlled trials evaluating interventions designed to promote residential smoke alarms. The following were assessed: smoke alarm acquisition, ownership, and function; fires; burns; and fire related injuries. Odds ratios (OR) were estimated by meta analysis of randomised trials. RESULTS: A total of 26 trials were identified, of which 13 were randomised. Overall, counselling and educational interventions had only a modest effect on the likelihood of owning an alarm (OR = 1.26; 95% confidence interval (CI): 0.87 to 1.81) or having a functional alarm (OR = 1.19; 95% CI: 0.85 to 1.66). Counselling as part of primary care child health surveillance had greater effects on ownership (OR = 1.93; 95% CI: 1.04 to 3.58) and function (OR = 1. 72; 95% CI: 0.78 to 3.78). Results were sensitive to trial quality, however, and effects on fire related injuries were not reported. In two non-randomised trials, direct provision of free alarms significantly increased functioning alarms and reduced fire related injuries. Media and community education showed little benefit in non-randomised trials. CONCLUSION: Counselling as part of child health surveillance may increase smoke alarm ownership and function, but its effects on injuries are unevaluated. Community smoke alarm give away programmes apparently reduce fire related injuries, but these trials were not randomised and results must be interpreted cautiously. Further efforts to promote smoke alarms in primary care or through give away programmes should be evaluated by adequately designed randomised controlled trials measuring injury outcomes.

Burns↗
PubMed2000

Radiolabeled annexin V imaging: diagnosis of allograft rejection in an experimental rodent model of liver transplantation.

PURPOSE: To assess the value of imaging rejection-induced apoptosis with technetium 99m and annexin V, a human protein-based radiopharmaceutical used in the diagnosis of acute rejection of a liver transplant, in a well-characterized rodent model of orthotopic liver transplantation. MATERIALS AND METHODS: 99mTc-radiolabeled annexin V was intravenously administered to six allografted (immunologically mismatched) and five isografted (immunologically matched) recipient rats on days 2, 4, and 7 after orthotopic liver transplantation. Animals were imaged 1 hour after injection of 0.2-2.0 mCi (8.0-74.0 MBq) of radiolabeled annexin V by use of clinical nuclear scintigraphic equipment. RESULTS: All animals in the allografted group demonstrated marked increases of 55% and 97% above the activity in the isografted group in hepatic uptake of annexin V on days 4 and 7, respectively. Severe acute rejection was histologically detected in all allografted livers on day 7. There was no histologic evidence of acute rejection in isografted animals. Dynamic hepatobiliary imaging with 99mTc and mebrofenin, an iminodiacetic acid derivative, demonstrated no correlation with the presence or absence of acute rejection or with annexin V uptake. CONCLUSION: Noninvasive imaging with radiolabeled annexin V is more sensitive and specific than imaging with 99mTc-mebrofenin in the diagnosis of acute rejection of a liver transplant.

Acute Disease↗
PubMed2000

Peripheral T-cell lymphoma complicated by a proliferation of large B cells.

We studied 14 cases that showed a morphologic appearance of peripheral T-cell lymphoma and contained substantial numbers of CD20+ large B cells. In all but 2 cases, the CD20+ large cells showed a mix of kappa and lambda light chain expression. Two cases showed a focal predominance of kappa expression. In situ hybridization using the EBER1 probe for detection of Epstein-Barr virus (EBV) RNA was performed on every case. EBV RNA was present in 10 cases. Of 8 cases with EBV RNA stained by immunohistochemistry for the latent membrane protein of EBV, 6 were positive. Double-labeling immunohistochemistry and in situ hybridization confirmed that EBV was present in the large B cells. Polymerase chain reaction (PCR) analysis showed a clonal rearrangement of the T-cell receptor (TCR)-gamma chain gene in 12 of 13 cases tested. One additional case showed a clonal rearrangement of the TCR-beta chain gene by Southern blot hybridization. PCR analysis showed a clonal immunoglobulin gene rearrangement in 5 cases, a suggestion of a clonal rearrangement in 1, an oligoclonal pattern in 4, and a polyclonal pattern in 4. The finding of large B and T cells may result in a misdiagnosis of a reactive process or of T-cell-rich B-cell lymphoma. The presence of EBV in some cases could cause further confusion with the reactive T- and B-immunoblastic proliferation of infectious mononucleosis.

Adult↗
PubMed2000

Large B-cell lymphoma of thyroid. Two cases with a marginal zone distribution of the neoplastic cells.

We report 2 cases of B-cell lymphoma of the thyroid in which although a marginal zone distribution of the neoplastic cells was present, the cytologic features of the cells indicated large cell lymphoma. One of the cases showed an accumulation of crystalline inclusions within the cytoplasm of the neoplastic cells. Many of these inclusion-bearing cells showed plasmacytoid features. By immunohistochemical studies performed on formalin-fixed paraffin-embedded tissue, both of the cases showed a B-cell phenotype as indicated by CD20 expression, and 1 showed kappa light chain restriction. In both cases, Ki-67 staining corroborated the impression of an aggressive neoplasm with staining of 50% and 90% of the tumor cells. Both patients received cyclophosphamide, doxorubicin, vincristine, and prednisone with radiation therapy, and both are without evidence of disease after 17 and 18 months of follow-up. It is important to recognize this pattern of large B-cell lymphoma of the thyroid gland. While the indolent course typical of most low-grade extranodal marginal zone lymphomas is not likely in these cases, the outcome may be favorable if patients are treated aggressively with therapy for large cell lymphoma.

Adenocarcinoma↗
PubMed1999

Herpes lymphadenitis in association with chronic lymphocytic leukemia.

BACKGROUND: Herpes simplex virus (HSV) infections range in severity from common cutaneous outbreaks to life-threatening central nervous system and deep organ involvement. HSV lymphadenitis is extremely rare but occurs both as a component of widely disseminated disease and as a localized, mild illness. METHODS: Five patients with chronic lymphocytic leukemia (CLL) underwent lymph node biopsy and were found to have histologic and immunophenotypic evidence of HSV infection in association with CLL. RESULTS: The patients were 3 males and 2 females ranging in age from 50 to 86 years. Only 1 patient had clinical evidence of cutaneous herpes at any time; in that patient, herpes lymphadenitis preceded the cutaneous herpes by 3 years. Four patients received no therapy for herpes at any time, whereas one was treated with intravenous and oral acyclovir. One patient died of CLL approximately 20 months after herpes lymphadenitis was diagnosed. The remaining four patients are alive with CLL. No patient had a fulminant clinical course related to HSV or developed disseminated infection. CONCLUSIONS: Herpes lymphadenitis may not have a fulminant course even in immunosuppressed CLL patients, even if they receive no antiviral therapy.

Aged↗
PubMed1999

Beta2-adrenergic receptor overexpression in the developing mouse heart: evidence for targeted modulation of ion channels.

1. We studied the effect of overexpression of the beta2-adrenergic receptor (beta2-AR) in the heart on ion channel currents in single cells isolated from hearts of fetal and neonatal transgenic and wild-type mice. The beta2-AR transgene construct was under the control of the murine alpha-myosin heavy chain (alpha-MHC) promoter, and ion channel activity was measured at distinct developmental stages using whole-cell and perforated patch clamp techniques. 2. We found no change in L-type Ca2+ channel current (ICa) density in early embryonic stages (E11-13) of beta2-AR transgenic positive (TG+) mice, but significant increases in ICa density in intermediate (E14-16, 152 %) and late (E17-19, 173.7 %) fetal and neonatal (1 day post partum, 161 %) TG+ compared with transgenic negative (TG-) mice. This increase in ICa was accompanied by a negative shift in the peak of the current-voltage relationship in TG+ mice. 3. Transient (< 3 min) or prolonged (16-24 h) exposure of TG- neonatal stage myocytes to 8-Br-cAMP (300 microM) increased ICa density and caused a shift in the current-voltage relationship to a similar extent to that seen in TG+ mice. In TG+ myocytes, 8-Br-cAMP had no effect. Exposure of TG+ cells to Rp-cAMPS reversed both the shift in voltage dependence and reduced the peak current density observed in these myocytes. We concluded from these results that the L-type Ca2+ channel is maximally modulated by cAMP-dependent protein kinase (PKA) in TG+ mice and that the alpha-MHC promoter is functional in the ventricle as early as embryonic day 14. 4. In contrast, we found that slow delayed rectifier K+ channels were not changed significantly at any of the developmental stages studied by the overexpression of beta2-ARs compared with TG- mice. The sensitivity of murine slow delayed rectifier K+ channels to cAMP was tested by both transient and prolonged exposure to 8-Br-cAMP (300 microM), which increased the slow delayed rectifier K+ channel current (IK,s) density to a similar extent in both TG- and TG+ neonatal myocytes. In addition, we found that there was no difference in the concentration dependence of the response of ICa and IK,s to 8-Br-cAMP. 5. Thus, overexpression of the beta2-AR in the heart results in distinct modulation of ICa, but not IK,s, and this is not due to differences in the 8-Br-cAMP sensitivity of the two channels. Instead, these results are consistent with both compartmentalization of beta2-AR-controlled cAMP and distinct localization of L-type Ca2+ and slow delayed rectifier K+ channels. This cAMP is targeted preferentially to the L-type Ca2+ channel and is not accessible to the slow delayed rectifier K+ channel.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1999

Mediastinal bronchogenic cyst manifesting as a catastrophic myocardial infarction.

Congenital bronchogenic cysts of the lung and mediastinum develop from the ventral foregut during embryogenesis. These cysts are often incidental radiologic findings in adults, but patients can be seen with symptoms of chest pain, cough, dyspnea, or any combination of these. Acute presentations are unusual and have rarely been reported. We present the unique case of a 36-year-old man seen with an acute coronary syndrome and sudden hemodynamic collapse. The patient sustained a massive and ultimately fatal myocardial infarction, compression of the left main coronary artery by a bronchogenic cyst was demonstrated at postmortem examination. If detected, bronchogenic cysts should be surgically excised to limit associated morbidity and mortality.

Adult↗
PubMed1999

CD30 expression is common in mediastinal large B-cell lymphoma.

Large B-cell lymphoma manifesting in the mediastinum shows distinctive clinical and immunophenotypic features and is recognized as a unique type of large B-cell lymphoma in the Revised European-American Lymphoma classification. Fifty-one cases of primary mediastinal large B-cell lymphoma were retrieved from the immunodiagnosis laboratory database files and were stained with anti-CD30 (Ber-H2). Of the 51 cases, 35 (69%) stained for CD30. This staining ranged from strong membrane staining of all or almost all of the neoplastic cells to positivity of rare individual cells. Eleven cases (22%) were negative; 4 (8%) were equivocal. Only 1 case was uninterpretable owing to B-5 fixation and lack of a positive internal control. Thus, the majority of mediastinal large B-cell lymphomas express the Hodgkin marker CD30. This finding may result in misdiagnosis of large cell lymphoma as Hodgkin disease.

Adolescent↗
PubMed1999

Meta-analysis.

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Humans↗