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Jacobs P, Wood L, Close P. Myeloma Presenting with Massive Splenomegaly. ACTA ACUST UNITED AC 1998; 3:375-9. [PMID: 27414081 DOI: 10.1080/10245332.1998.11746411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Myeloma typically presents with skeletal damage, renal failure, metabolic disturbances and anaemia. Less usual associations are polyneuropathy, solitary plasmacytomas, and only rarely is lymphadenopathy found. Discomfort and left upper quadrant pain due to marked splenomegaly appears unknown, particularly as the initial symptom. Accordingly, two cases are reported in which this was the reason for seeking medical attention. In both splenectomy was unavoidable because of size and symptomatic infarction. The dominant histologic feature in the first was striking proliferation of sinus lining cells engorged with the IgA paraprotein. In the second there was dramatic expansion of the red pulp. In neither, despite using appropriate immunohistochemical techniques, could the enlargement of the spleen be attributed to infiltration by plasma cells that in the peripheral and blood and marrow had a distinctively unusual morphology. In these two individuals the pathophysiology remains obscure. In the first, although considered, it was not possible to meet the criteria for this being an example of littoral cell angioma. In the second, a postulated disseminated plasmacytoma with primary splenic sequestration remains unproven. This unique finding is, therefore, presented as descriptive pathology without recognisable explanation.
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Grindstaff PD, Kreider R, Bishop R, Wilson M, Wood L, Alexander C, Almada A. Effects of creatine supplementation on repetitive sprint performance and body composition in competitive swimmers. INTERNATIONAL JOURNAL OF SPORT NUTRITION 1997; 7:330-46. [PMID: 9407259 DOI: 10.1123/ijsn.7.4.330] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In a double-blind and randomized manner, 18 male and female junior competitive swimmers supplemented their diets with 21 g.day-1 of creatine monohydrate (Cr) or a maltodextrin placebo (P) for 9 days during training. Prior to and following supplementation, subjects performed three 100-m freestyle sprint swims (long course) with 60 s rest/recovery between heats. In addition, subjects performed three 20-s arm ergometer maximal-effort sprint tests in the prone position with 60 s rest/recovery between sprint tests. Significant differences were observed among swim times, with Cr subjects swimming significantly faster than P subjects following supplementation in Heat 1 and significantly decreasing swim time in the second 100-m sprint. There was also some evidence that cumulative time to perform the three 100-m swims was decreased in the Cr group. Results indicate that 9 days of Cr supplementation during swim training may provide some ergogenic value to competitive junior swimmers during repetitive sprint performance.
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Jacobs P, Wood L. Hazards of interferon therapy in chronic granulocytic leukaemia. S Afr Med J 1997; 87:1394. [PMID: 9472263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Grindel CG, Bayley E, Kingston MB, Tuck MB, Wood L, Bryan Y. Nurses preparing for change: their needs and concerns. MEDSURG NURSING : OFFICIAL JOURNAL OF THE ACADEMY OF MEDICAL-SURGICAL NURSES 1997; 6:278-83, 286-7. [PMID: 9384154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
As a result of decreased lengths of stay and cost-containment initiatives, fewer nurses are needed in acute care settings. The trend for community-based health care is broadening employment opportunities for nurses to work in community settings. As nurses are considering options to base their practice in community settings, it is important to understand their concerns about making this transition. The results of a qualitative study conducted to examine the concerns and educational needs of acute care nurses related to working in the community are reported. Clinical, professional, and intrapersonal skills important for a successful transition to community-based practice are identified and discussed.
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Van Deusen MA, Angelini BL, Cordoro KM, Seiler BA, Wood L, Skoner DP. Efficacy and safety of oral immunotherapy with short ragweed extract. Ann Allergy Asthma Immunol 1997; 78:573-80. [PMID: 9207721 DOI: 10.1016/s1081-1206(10)63218-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Oral immunotherapy, if proven safe and effective, could be an alternative to subcutaneous immunotherapy. OBJECTIVE This pilot study investigated the clinic and immunologic effects of ragweed immunotherapy using a new microencapsulated, pH-sensitive, oral delivery system. METHODS A double-blind, placebo-controlled trial was conducted in 23 patients with allergic rhinitis to short ragweed. Following a baseline nasal challenge with ragweed allergen, oral immunotherapy with encapsulated short ragweed extract or placebo was administered once daily, 6 days/week. Dosed began at 3 micrograms Amb a 1 per day and were increased by 3 micrograms every three days as tolerated, to a maximum daily maintenance dose of 24 micrograms. A nasal challenge was repeated 6 weeks, later, followed by the continuation of maintenance therapy through the natural ragweed season. Daily allergy symptoms and relief medication usage was recorded. A final nasal challenge was performed at the end of the natural season. Short ragweed-specific serum IgE, IgG, and IgG4 antibody levels were measured every 2 weeks during the study. RESULTS Maximum tolerated doses ranged from 6 to 24 micrograms Amb a 1 per day (74% reached 24 micrograms). Adverse events were not serious or different between the active and placebo groups. The active group showed increased in short ragweed-specific serum IgG and IgG4 antibody levels. Symptom scores during the natural season were numerically but not statistically lower in the active treatment group. This group also experienced a greater reduction from baseline in nasal reactivity as assessed by nasal challenge. CONCLUSIONS These pilot data suggest that the encapsulated, pH-sensitive oral immunotherapy delivery system was safe, induced a brisk serologic response, and attenuated the symptomatic response to both experimental and environmental ragweed exposure.
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Denburg JA, Inman MD, Wood L, Ellis R, Sehmi R, Dahlback M, O'Byrne P. Bone marrow progenitors in allergic airways diseases: studies in canine and human models. Int Arch Allergy Immunol 1997; 113:181-3. [PMID: 9130516 DOI: 10.1159/000237540] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In a canine model of Ascaris suum-inducible bronchial hyperresponsiveness, we previously demonstrated that bone marrow-derived myeloid progenitors rise within 24 h of allergen inhalation; this effect is abolished by pretreatment with inhaled budesonide. We now report that this allergen-induced bone marrow response is observable in human asthmatics, and involves increases in both neutrophil-macrophage and eosinophil-basophil progenitors, within 6 h of allergen inhalation, as measured either by hematopoietic colony assays or by flow cytometric analyses of CD34+, IL-3R alpha+, and/or IL-5-responsive cell populations. In dogs, but not in humans, a transferrable serum hematopoietic activity accounts for the marrow response to inhaled allergen. These findings suggest that allergen-induced increases in bone marrow progenitor formation depend either on a serum hematopoietic factor(s) released after allergen challenge, or upon constitutive marrow upregulation of specific progenitors in allergic airway disease. Further studies to characterize the serum hematopoietic factor(s) and to determine the nature of any atopy-related progenitor profile are in progress.
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Boles M, Wood L. Mental health. Home at last. THE HEALTH SERVICE JOURNAL 1997; 107:34. [PMID: 10165740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Jacobs P, Wood L, Barendse G, Maresky A. Reversal of Life-Threatening Vascular Occlusion by Apheresis in Fulminating Plasmodium Falciparum Malaria. ACTA ACUST UNITED AC 1997; 2:257-60. [PMID: 27406871 DOI: 10.1080/10245332.1997.11746345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Plasmodium falciparum parasitisation can result in a systemic inflammatory response characterised by profound neurologic complications, renal failure, adult respiratory distress syndrome and disseminated intravascular coagulation with high morbidity and mortality. Complete obstruction to medium sized arteries seems not to have been reported before while the role of sequential whole blood and plasma exchange may be an under-utilised intervention that is life-saving in selected cases. A 25 year old patient was referred with mental confusion, rapidly deteriorating vision, hypotensive and oliguric, massive generalised oedema compressing muscles leading to rhabdomyolysis and impending gangrene of both lower limbs. 1,555 mL of whole blood was exchanged in the cell separator to reverse the haemoglobin of 35g/L, remove parasitised and effete red cells while simultaneously correcting hypovolaemia. Thereafter 4,000mL of fresh frozen plasma was similarly exchanged and 3 × 10(11) platelets given to treat the advanced disseminated intravascular coagulation. Anti-malarial therapy was continued with quinine sulphate and doxycycline for the chloroquin-resistant parasites. The tense swelling of the limbs gradually resolved, thereby avoiding fasciotomies, arterial occlusion reversed and microvascular perfusion was re-established with resolution of all symptoms. Tissue loss was eventually limited to fore foot amputation on the left. The patient has been physically and psychologically rehabilitated and discharged after six weeks in hospital. Malaria, when associated with multiple organ failure, is frequently fatal. Where appropriate, complications-due to vascular occlusion-can be promptly reversed with suitable apheresis. This practical approach is relatively inexpensive and should be available in all centres responsible for managing such patients.
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Jacobs P, Wood L, Byrne M, Jackson G, Blewett R, Marais D, Firth J. Iron Deficiency Developing in Patients with Homozygous Hypercholesterolaemia on Long-term Plasmapheresis is Significantly Contributed to by Extracorporeal Haemolysis. Hematology 1997; 2:497-505. [PMID: 27415847 DOI: 10.1080/10245332.1997.11746372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Patients with homozygous hypeicholesterolaemia are notoriously refractory to pharmacologic intervention, leaving regular long-term plasmapheresis as one of the most effective forms of therapy. In this situation we noted the universal development of anaemia; accordingly, its pathogenesis was investigated in a stable cohort of patients over a two year period. Radionuclide studies were carried out in 8 of the 9 available individuals: of these 3 who were not on treatment and 3 out of 5 on the apheresis programme had mean red cell lifespan below the lower level of our normal range. The creation of an arterio-venous fistula and subsequent performance of plasma exchange procedures every two weeks was followed by a falling haemoglobin concentration and the appearance of hypochromasia and microcytosis. The latter was the result of substantial loss of iron through venesection, in the discard plasma and by a transient peak of the iron in the urine: the last two compartments were studied using inductively coupled plasma atomic emission spectrometry (ICP-AES). Such depletion could not be compensated for by a dietary intake of iron that barely met the recommended daily allowance whereas the anaemia reversed readily on oral supplementation. This is the first report of extracorporeal haemolysis in this clinical setting and recognition of its pathophysiology directly influences management. Thus, oral iron supplementation should prevent anaemia and its symptoms whilst also circumventing the paradoxical hyperviscosity that might otherwise occur from iron deficiency.
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Puddicombe SM, Wood L, Chamberlin SG, Davies DE. The interaction of an epidermal growth factor/transforming growth factor alpha tail chimera with the human epidermal growth factor receptor reveals unexpected complexities. J Biol Chem 1996; 271:30392-7. [PMID: 8940002 DOI: 10.1074/jbc.271.48.30392] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
It has been assumed that substitution of homologous regions of transforming growth factor alpha (TGF-alpha) into epidermal growth factor (EGF) can be used to probe ligand-receptor recognition without detrimental effects on ligand characteristics for the human EGF receptor (EGFR). We show that a chimera of murine (m) EGF in which the carboxyl-terminal tail is substituted for that of TGF-alpha (mEGF/TGF-alpha44-50) results in complex features that belie this initial simplistic assumption. Comparison of EGF and mEGF/TGF-alpha44-50 in equilibrium binding assays showed that although the relative binding affinity of the chimera was reduced 80-200-fold, it was more potent than EGF in mitogenesis assays using NR6/HER cells. This superagonist activity could not be attributed to differences in ligand processing or to binding to other members of the c-erbB family. It appeared to be due, in part, to choice of an EGFR-overexpressing target cell where high receptor number compensated for the low affinity of the ligand; it also appeared to be related to the ability of the chimera to activate the EGFR tyrosine kinase. Thus, when EGFR autophosphorylation was measured, mEGF/TGF-alpha44-50 was more potent than EGF, despite its low affinity. When tested using chicken embryo fibroblasts, substitution of the TGF-alpha carboxyl-terminal tail into mEGF failed to enhance its binding affinity for chicken EGFRs; however, the chimera was intermediate in potency between TGF-alpha and mEGF in mitogenesis assays. Our results suggest a contextual requirement for EGFR recognition which is ligand-specific. Further, the unpredictable responses to chimeric ligands underline the complex nature of the processes of ligand recognition, receptor activation, and the ensuing cellular response.
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Wood L. Perinatal transmission of HIV-1. JAMA 1996; 276:1300-1; author reply 1301. [PMID: 8861985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Kreider RB, Klesges R, Harmon K, Grindstaff P, Ramsey L, Bullen D, Wood L, Li Y, Almada A. Effects of ingesting supplements designed to promote lean tissue accretion on body composition during resistance training. INTERNATIONAL JOURNAL OF SPORT NUTRITION 1996; 6:234-46. [PMID: 8876343 DOI: 10.1123/ijsn.6.3.234] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This study examined the effects of ingesting nutritional supplements designed to promote lean tissue accretion on body composition alterations during resistance training. Twenty-eight resistance-trained males blindly supplemented their diets with maltodextrin (M), Gainers Fuel 1000 (GF), or Phosphagain (P). No significant differences were observed in absolute or relative total body water among groups. Energy intake and body weight significantly increased in all groups combined throughout the study with no group or interaction differences observed. Dual energy x-ray absorptiometry-determined body mass significantly increased in each group throughout the study with significantly greater gains observed in the GF and P groups. Lean tissue mass (excluding bone) gain was significantly greater in the P group, while fat mass and percent body fat were significantly increased in the GF group. Results indicate that total body weight significantly increased in each group and that P supplementation resulted in significantly greater gains in lean tissue mass during resistance training.
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Jacobs P, Wood L. The lymphomas. THE CENTRAL AFRICAN JOURNAL OF MEDICINE 1996; 42:273-80. [PMID: 8997823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hodgkin's disease and the malignant lymphomas are, by all available evidence, eminently curable neoplasms. The debates, therefore, on how best the largest numbers of individuals in any community can receive appropriate treatment and this implies their ready access to an experienced multi disciplinary combined clinic. It is important that proper perspective be retained in the African context so that preventive medicine can be employed where appropriate but, based on current understanding, those with lymphoreticular malignancy become immediate beneficiaries of whatever diagnostic and therapeutic resources need to be expended in ensuring optimal outcome. The last word is far from written on how we, as inhabitants of the African continent, will achieve this goal and so measure up to our obligation. However, as resources continue to contract, three observations justify reiteration. Firstly, diagnostic skills need to be honed by experienced pathologists together reviewing all biopsy material and, wherever possible, participating in national or international study groups. Secondly, the silly distinction propagated by some self serving individuals who fantasize that state hospitals and private clinics somehow differ, must be replaced by a more responsible attitude in which resources are pooled in the common quest for maintaining academic standards. Thirdly, given acceptance of the above common sense proposals, a mechanism will exist for the establishment and constant upgrading of national guidelines for management on agreed and achievable protocols. Whilst the theme remains that of tested conventional treatment, flexibility must exist, where appropriate, for palliative care on the one hand with scientific growth and exploration of innovative options on the other. One might conclude by observing that Africa is most certainly unique and this extends to the frequency with which some of these tumours occur; a classical example would be Burkitt's Lymphoma. This places an obligation on all of us to gather and record such experiences and, from this basis, sustain our intellectual drive by forging international bonds with colleagues in the First World. Such collaboration will provide the natural bridge between clinical studies in Africa and the more sophisticated cellular and molecular biology that is being provided by basic scientists in other parts of the world. Such a marriage is practical and both parties stand to gain significantly in the research, development and evaluation of new drugs and protocols that, ultimately, serve the best interests of patients and do so on a world-wide basis.
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du Toit JM, Kaftansky R, Wood L, Jacobs P. A risk-to-benefit analysis for central venous catheters. TRANSFUSION SCIENCE 1996; 17:379-83. [PMID: 10163544 DOI: 10.1016/0955-3886(96)00008-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Reliable venous access is an important consideration in the management of the cancer patient, where long-term intravenous therapy is needed. A single institution retrospective analysis of 205 catheter placements allowed comparison of different lines and techniques. This experience shows that surgical introduction under general anaesthetic of a double-lumen, 12 gauge, silastic catheter in the superior vena cava, via the internal jugular vein and using a 15 cm anterior chest wall tunnel, resulted in longest survival, fewest infections, and enjoyed a high patient acceptability. A substantial cost-saving, particularly in antibiotic usage, was observed as a result of the improved technique.
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Pillay GS, Wood L, Jacobs P. Fludarabine monophosphate as salvage for refractory chronic lymphocytic leukaemia. S Afr Med J 1996; 86:949-51. [PMID: 8823419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVE To assess the efficacy of the purine analogue fludarabine monophosphate (FAMP) as salvage therapy in patients at Groote Schuur Hospital with chronic lymphocytic leukaemia (CLL) refractory to standard therapy. DESIGN Non-randomised trial. SETTING Tertiary care, referral academic hospital. PATIENTS Seven patients with B-lineage CLL, 4 in Rai stage IV and 1 each in stages A(I), A(II) and A(III), refractory to treatment with chlorambucil or cyclophosphamide, with or without whole-body irradiation. INTERVENTION Intravenous FAMP at a dose of 25 mg/m2 daily for 5 days every 28 days. MAIN OUTCOME MEASURES Partial remission, complete remission, stable disease or progressive disease. RESULTS Two patients entered CR and 4 PR after a median of 8 courses of treatment (range 2 - 12). One patient died of Pneumocystis carinii pneumonia after 3 courses of therapy. The most common adverse effect of the treatment was myelosuppression, with the nadir of neutrophil counts being less than 0.5 x 10(9)/1 in 5 patients. Three developed infections and required hospitalisation while on therapy. CONCLUSION FAMP is effective as a cytoreductive agent in patients with CLL refractory to alkylating agents, with or without whole-body irradiation.
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Armstrong RA, Wood L, Myers D, Smith CU. The use of multivariate methods in the identification of subtypes of Alzheimer's disease: a comparison of principal components and cluster analysis. DEMENTIA (BASEL, SWITZERLAND) 1996; 7:215-20. [PMID: 8835886 DOI: 10.1159/000106882] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Two contrasting multivariate statistical methods, viz., principal components analysis (PCA) and cluster analysis were applied to the study of neuropathological variations between cases of Alzheimer's disease (AD). To compare the two methods, 78 cases of AD were analyzed, each characterised by measurements of 47 neuropathological variables. Both methods of analysis revealed significant variations between AD cases. These variations were related primarily to differences in the distribution and abundance of senile plaques (SP) and neurofibrillary tangles (NFT) in the brain. Cluster analysis classified the majority of AD cases into five groups which could represent subtypes of AD. However, PCA suggested that variation between cases was more continuous with no distinct subtypes. Hence, PCA may be a more appropriate method than cluster analysis in the study of neuropathological variations between AD cases.
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Lewis LL, Venzon D, Church J, Farley M, Wheeler S, Keller A, Rubin M, Yuen G, Mueller B, Sloas M, Wood L, Balis F, Shearer GM, Brouwers P, Goldsmith J, Pizzo PA. Lamivudine in children with human immunodeficiency virus infection: a phase I/II study. The National Cancer Institute Pediatric Branch-Human Immunodeficiency Virus Working Group. J Infect Dis 1996; 174:16-25. [PMID: 8655986 DOI: 10.1093/infdis/174.1.16] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The safety, tolerability, pharmacokinetic profile, and preliminary activity of lamivudine (2'-deoxy-3'-thiacytidine), a novel cytidine nucleoside analogue with antiretroviral activity, in human immunodeficiency virus (HIV)-infected children beyond the neonatal period were studied. Ninety children received dosages of 1-20 mg/kg/day. Pharmacokinetic evaluation demonstrated serum and cerebrospinal fluid concentrations that increased proportionally to dose. As of January 1994, 11 children had been withdrawn from study for disease progression and 10 because of possible lamivudine-related toxicity, and 6 had died. CD4 and CD8 cell counts remained stable over 24 weeks in therapy-naive children and decrease slightly in previously treated children. Quantitative immune complex-dissociated p24 antigen and HIV RNA were decreased significantly at 12 and 24 weeks. In vitro resistance to lamivudine was documented in sequential virus isolates from some patients by 12 weeks. Lamivudine was well-tolerated and exhibited virologic activity in children, although future use in children is likely to be in combination antiretroviral regimens.
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Puddicombe SM, Chamberlin SG, MacGarvie J, Richter A, Drummond DR, Collins J, Wood L, Davies DE. The significance of valine 33 as a ligand-specific epitope of transforming growth factor alpha. J Biol Chem 1996; 271:15367-72. [PMID: 8663070 DOI: 10.1074/jbc.271.26.15367] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Although binding of epidermal growth factor (EGF) and transforming growth factor alpha (TGFalpha) to the EGF receptor (EGFR) is mutually competitive, their binding is not identical, and their biological activities are not always equivalent. To probe for ligand-specific interactions, we have synthesized analogues of TGFalpha with modifications to the residue lying between the fourth and fifth cysteines (the "hinge"). Although this residue lies in a structurally conserved region of the protein, it is not conserved within the EGFR ligand family. Our results show that in TGFalpha there is a preference for a bulky hydrophobic hinge residue; this contrasts with EGF, for which a hydrogen bond donor functionality is preferred. Sequence analysis of the human EGFR ligands revealed that the nature of the hinge residue correlated with the sequence in the B-loop beta-sheet. As this region is an important determinant in recognition of TGFalpha by the chicken EGFR, we assessed the mitogenicity of the TGFalpha hinge mutants, as well as the other EGFR ligands, using chicken embryo fibroblasts. The preference of the chicken EGFR for TGFalpha hinge mutants with hydrophobic side chains paralleled that of the human EGFR. Betacellulin and heparin-binding EGF-like growth factor also possess an hydrophobic hinge; both were at least as potent as TGFalpha for chicken embryo fibroblasts. EGF and amphiregulin, both with hydrogen bond donor functionalities at their hinge, displayed markedly decreased in potency by comparison with TGFalpha. We propose that EGFR ligands can be subclassified into TGFalpha-like and EGF-like and that this is of functional significance, identifying a potential mechanism whereby EGFR can discriminate between its ligands.
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Wood L. Frequency and chronological distribution of linear enamel hypoplasia in a North American colonial skeletal sample. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 1996; 100:247-59. [PMID: 8771314 DOI: 10.1002/(sici)1096-8644(199606)100:2<247::aid-ajpa6>3.0.co;2-u] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A skeletal sample of 44 individuals born and raised in early 18th century frontier settlements of Northeastern United States is examined for the frequency and chronological distribution of linear enamel hypoplasia (LEH) on the maxillary and mandibular incisors and canines. The prevalence of LEH ranged from 31% on the I2 to 66% on the mandibular C and the mean number of defects ranged from .59 on the I2 to 1.08 on the mandibular C. These frequencies were generally lower than those reported for two later samples; the Monroe County Poorhouse sample and the Hammon-Todd sample. Individuals in these latter two samples were derived from the lowest socioeconomic stratum of their respective populations. Frequency differences are explained within the context of the changing availability of resources that resulted from the rise of industrialization, urbanization, and wage labor which took place during the 18th and 19th centuries. The frequency of LEH was low prior to 1.5 years of age and may result from attrition and/or decreased susceptibility in the relevant area of the crown or from low morbidity or high mortality. Peak frequencies are observed in all age categories ranging from 2.5 to 3.0 years up to 4.0 to 4.5 years and are too late to result from weaning. Instead, they may reflect the susceptibility of nonimmune children to diseases that were common in colonial North America. As the majority of these diseases were not fatal, most victims who survived may have had one or more LEHs as visible proof of their earlier encounter(s).
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Almada A, Kreider R, Weiss L, Fry A, Wood L, Bullen D, Miyaji M, Grindstaff P, Ramsey L, Li Y. EFFECTS OF INGESTING A SUPPLEMENT CONTAINING CREATINE MONOHYDRATE FOR 28 DAYS ON ISOKINETIC PERFORMANCE. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-00822] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Grindstaff P, Kreider R, Weiss L, Fry A, Wood L, Bullen D, Miyaji M, Ramsey L, Li Y, Almada A. EFFECTS OF INGESTING A SUPPLEMENT CONTAINING CREATINE MONOHYDRATE FOR 7 DAYS ON ISOKINETIC PERFORMANCE. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-00821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kreider R, Harman K, Klesges B, Weiss L, Fry A, Ramsey L, Grindstaff P, Miyaji M, Bullen D, Wood L, Li Y, Almada A. EFFECTS OF INGESTING NUTRITIONAL SUPPLEMENTS DESIGNED TO PROMOTE LEAN TISSUE ACCRETION ON BODY COMPOSITION. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-00951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zurlo JJ, Wood L, Gaglione MM, Polis MA. Effect of splenectomy on T lymphocyte subsets in patients infected with the human immunodeficiency virus. Clin Infect Dis 1995; 20:768-71. [PMID: 7795071 DOI: 10.1093/clinids/20.4.768] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A case-control study was conducted at two institutions to determine whether the absolute CD4 lymphocyte count or the percentage of lymphocytes bearing the CD4 marker (i.e., the CD4 percentage) is a more accurate indicator of underlying immune status in splenectomized patients infected with human immunodeficiency virus (HIV). Each of nine splenectomized HIV-infected cases was matched with six nonsplenectomized HIV-infected controls--three matched for CD4 lymphocyte count and three for CD4 percentage. In analyses including the eight cases with an initial CD4 lymphocyte count of > 200/mm3, controlling for the CD4 count revealed differences between cases and controls in terms of CD4 percentage (range, 10%-41% and 17%-54%, respectively; P < .01) and Centers for Disease Control and Prevention (CDC) clinical stage (P = .06). Controlling for the CD4 percentage revealed a significant difference between cases and controls in terms of CD4 count (range, 396-1,040 and 55-784 cells/mm3, respectively; P < .01) but not CDC clinical stage (P > .7). These data suggest that the numerical relationship between the CD4 lymphocyte count and the CD4 percentage among splenectomized HIV-infected patients with more than 200 CD4 cells/mm3 differs from that among nonsplenectomized patients. The CD4 percentage appears to be a more accurate indicator of the underlying level of immune function in the former group of patients.
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Wood L. Induction of labour confers benefit in prolonged pregnancy. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1994; 101:1102. [PMID: 7826976 DOI: 10.1111/j.1471-0528.1994.tb13604.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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