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Perception of effort during an isometric contraction is influenced by prior muscle lengthening or shortening. Eur J Appl Physiol 2021; 121:2531-2542. [PMID: 34080065 DOI: 10.1007/s00421-021-04728-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/20/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE Following a shortening or lengthening muscle contraction, torque produced in the isometric steady state is lower (residual torque depression; rTD) or higher (residual torque enhancement; rTE), respectively, compared to a purely isometric contraction at the same final muscle length and level of activation. This is referred to as the history dependence of force. When matching a given torque level, there is greater muscle activation (electromyography; EMG) following shortening and less activation following lengthening. Owing to these differences in neuromuscular activation, it is unclear whether perception of effort is altered by the history dependence of force during plantar-flexion. METHODS Experiment 1 tested whether perception of effort differed between the rTD and rTE state when torque was matched. Experiment 2 tested whether perception of effort differed between the rTD and rTE state when EMG was matched. Finally, experiment 3 tested whether EMG differed between the rTD and rTE state when perception of effort was matched. RESULTS When torque was matched, both EMG and perception of effort were higher in the rTD compared to rTE state. When EMG was matched, torque was lower in the rTD compared to rTE state while perception of effort did not differ between the two states. When perception of effort was matched, torque was lower in the rTD compared to rTE state and EMG did not differ between the two states. CONCLUSION The combined results from these experiments indicate that the history dependence of force alters one's perception of effort, dependent on the level of motor command.
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Reducing risk of Type 2 diabetes in HIV: a mixed-methods investigation of the STOP-Diabetes diet and physical activity intervention. Diabet Med 2020; 37:1705-1714. [PMID: 30734352 DOI: 10.1111/dme.13927] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/05/2019] [Indexed: 12/14/2022]
Abstract
AIM To conduct a mixed-methods feasibility study of the effectiveness and acceptability of an individualized diet and physical activity intervention designed to reduce the risk of Type 2 diabetes experienced by people living with HIV. METHODS Participants with impaired fasting glucose and HIV were invited to take part in a 6-month diet and physical activity intervention. Individualized advice to achieve 10 lifestyle goals was delivered monthly. Diabetes risk was assessed pre- and post-intervention by measurement of the glucose and insulin response to a 3-h meal tolerance test. Six-month change was analysed using paired t-tests. Research interviews exploring the acceptability of the intervention and factors influencing behaviour change were conducted with those who participated in the intervention, and those who declined participation. RESULTS The intervention (n=28) significantly reduced the following: glucose and insulin, both fasting and postprandial incremental area under the curve (glucose 7.9% and 17.6%; insulin 22.7% and 31.4%, respectively); weight (4.6%); waist circumference (6.2%); systolic blood pressure (7.4%); and triglycerides (36.7%). Interview data demonstrated the acceptability of the intervention. However, participants expressed concern that deliberate weight loss might lead to disclosure of HIV status or association with AIDS-related illness. The belief that antiretroviral medications drove diabetes risk was associated with declining study participation or achieving fewer goals. CONCLUSIONS We have demonstrated the beneficial effects of a lifestyle intervention in mitigating the increased risk of Type 2 diabetes associated with HIV. Future interventions should be designed to further reduce the unique barriers that prevent successful outcomes in this cohort.
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Cardiovascular responses during isometric exercise following lengthening and shortening contractions. J Appl Physiol (1985) 2018; 126:278-285. [PMID: 30382808 DOI: 10.1152/japplphysiol.00601.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study investigated the effects of prior lengthening or shortening contractions on cardiovascular responses during isometric exercise. We utilized the history dependence of skeletal muscle, where active 2-s lengthening or shortening before an isometric contraction can increase [residual force enhancement (RFE)] or decrease [force depression (FD)] force production. Matching torque output between RFE and FD conditions yields lower and higher electromyography (EMG) values, respectively. In study 1, heart rate and perceived exertion (PE; Borg10) were measured in 20 participants during 20-s isometric plantar flexion contractions at low (16 ± 4% MVC)-, moderate (50 ± 5% MVC)-, and high (88 ± 7% MVC)-intensity. In study 2, heart rate and blood pressure were measured in 14 participants during 2-min isometric plantar flexion contractions (40% MVC). In both studies, torque output was held constant between FD and RFE conditions resulting in differences in soleus EMG activity ( P < 0.05). In study 1, PE was lower during the RFE condition ( P < 0.01), while increases in heart rate were similar between FD and RFE at low (∆2 ± 8 vs. 3 ± 6 beats/min, P > 0.99) and moderate (∆14 ± 9 vs. 14 ± 9 beats/min, P > 0.99) intensity but smaller during RFE at high intensity (∆35 ± 13 vs. 29 ± 13 beats/min, P = 0.004). In study 2, heart rate responses were smaller in the RFE condition following the initial 20-s period; diastolic blood pressure responses were smaller during the last 80 s. A 2-s active change in muscle length before an isometric contraction can influence heart rate and blood pressure responses; however, these differences appear to be modulated by both intensity and duration of the contraction. NEW & NOTEWORTHY Using the history dependence of isometric force to alter maximal torque production and motor unit activation between residual force enhancement and force depression conditions, we observed that heart rate responses were different between conditions during a subsequent 20-s high-, but not low- or moderate-, intensity isometric contraction. A 2-min moderate-intensity contraction revealed time-dependent effects on heart rate and diastolic blood pressure. Active 2-s shortening and lengthening before an isometric contraction can influence the cardiovascular responses.
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Abstract
Initial therapies for HIV infection comprised nucleoside analogues, but as single or dual agents, they failed to prevent disease progression. When a new class of drug was introduced, the protease inhibitors, an effective triple therapy became possible-namely, highly active antiretroviral therapy, or HAART. HAART reduced viral replication almost completely and enabled immune system recovery. The probability of classical infections and tumors attributed to HIV were dramatically reduced, and life expectancy correspondingly increased. The initial disadvantages of HAART included the need for strict adherence to prevent drug resistance, the cost that initially precluded their widespread use in the developing world, and the short- and long-term side effects. One of the most disabling long-term complications was HIV lipodystrophy, which in extreme cases lead to severe peripheral fat wasting and central fat gain. In recent years, many of these disadvantages have been addressed: Once-daily drug combinations improve adherence; global access to HAART has been markedly improved; and new drugs enable patients to avoid many of the initial side effects. Future research will determine at what CD4 count HAART should be initiated, and new approaches such as immunotherapeutic HIV vaccines are being tested with the aim to delay or obviate the need for antiretroviral drugs.
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Cardiovascular risk evaluation and antiretroviral therapy effects in an HIV cohort: implications for clinical management: the CREATE 1 study. Int J Clin Pract 2010; 64:1252-9. [PMID: 20653801 PMCID: PMC2913108 DOI: 10.1111/j.1742-1241.2010.02424.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
AIMS The aim of this study is to determine the cardiovascular disease (CVD) risk profile of a large UK HIV cohort and how highly active antiretroviral therapy (HAART) affects this. METHODS It is a cross-sectional study within a large inner city hospital and neighbouring district hospital. A total of 1021 HIV positive outpatients representative of the complete cohort and 990 who had no previous CVD were included in CVD risk analysis. We recorded demographics, HAART history and CVD risk factors. CVD and coronary heart disease (CHD) risks were calculated using the Framingham (1991) algorithm adjusted for family history. RESULTS The non-CVD cohort (n = 990) was 74% men, 51% Caucasian and 73.1% were on HAART. Mean age was 41 +/- 9 years, systolic blood pressure 120 +/- 14 mmHg, total cholesterol 4.70 +/- 1.05 mmol/l, high-density lipoprotein-C 1.32 +/- 0.48 mmol/l and 37% smoked. Median CVD risk was 4 (0-56) % in men and 1.4 (0-37) % in women; CHD risks were 3.5 (0-36) % and 0.6 (0-16) %. CVD risk was > 20% in 6% of men and 1% of women and > 10% in 12% of men and 4% of women. CVD risk was higher in Caucasians than other ethnicities; the risk factor contributing most was raised cholesterol. For patients on their first HAART, increased CHD risk (26.2% vs. 6.5%; odds ratio 4.03, p < 0.001) was strongly related to the duration of therapy. CONCLUSIONS Modifiable risk factors, especially cholesterol, and also duration of HAART, were key determinants of CVD risk. DISCUSSION Regular CHD and/or CVD risk assessment should be performed on patients with HIV, especially during HAART therapy. The effect of different HAART regimens on CHD risk should be considered when selecting therapy.
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Disseminated gonococcal infection in a homosexual man diagnosed by nucleic acid amplification testing from a skin lesion swab. Sex Transm Infect 2008; 84:348-9. [PMID: 18809698 DOI: 10.1136/sti.2008.030817] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Disseminated gonococcal infection (DGI) often presents a diagnostic challenge. Through the novel application of molecular technology, a case is presented that suggests how the diagnostic sensitivity for this systemic complication of gonococcal infection can be improved. In a typical case of DGI seen in a homosexual man in whom all mucosal and blood specimens were culture negative, nucleic acid amplification testing (NAAT) helped to confirm the diagnosis. Both throat and skin lesion specimens tested positive for gonococcal DNA and this was confirmed with a supplementary porA pseudogene NAAT. The use of adjuvant NAAT assessment is recommended as part of the diagnostic work-up for suspected DGI cases.
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Abstract
The drug treatments introduced in recent years for HIV infection have enabled a marked reduction in morbidity and prolongation of life. These treatments, however, are often associated with acute and chronic toxicities, the development of resistant virus can limit their effectiveness, and they are too expensive and difficult to administer in most third world settings. A successful HIV immunotherapeutic vaccine has the potential to overcome these problems, and would be a valuable advance. The most promising approaches have induced the type of immune response found to correlate with reduced activity of HIV in man, especially cytotoxic T-cell responses, or have led to reduced HIV or SIV viral load and increased CD4 counts in non-human primates or man. The agents that have led to one or both of these effects have been selected for review, and include inactivated envelope depleted virus, recombinant envelope glycoprotein, DNA vaccines utilising HIV peptides or gene products, viral vectors, such as canarypox or attenuated vaccinia, with HIV core proteins. There are other approaches, such as alloimmunity, for which no candidate products yet exist, but which conceptually appear promising. Currently, however, only a few phase III studies of HIV therapeutic vaccines have been completed in man, and there has been a modest therapeutic effect. Further development of both existing and new candidates remains one of the key priorities in our fight against HIV.
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Thalidomide is distributed into human semen after oral dosing. Drug Metab Dispos 2001; 29:1355-7. [PMID: 11560881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
As part of a double-blind placebo-controlled study of the effect of thalidomide on body weight and the viral load of human immunodeficiency virus-seropositive patients, plasma and semen samples were analyzed for the presence of thalidomide. Patients were orally dosed with 100 mg of thalidomide/day for 8 weeks. Blood samples were obtained at baseline and weeks 4, 8, and 12, and semen was obtained at baseline and weeks 4 and 8. Samples were extracted with solid-phase cartridges and analyzed by liquid chromatography/tandem mass spectrometry using atmospheric pressure chemical ionization in the negative ion mode. Two of four patients taking thalidomide were able to provide semen samples. Both had detectable levels of thalidomide in their plasma (10-350 ng/ml) and semen (10-250 ng/g) at weeks 4 and 8. There was an apparent correlation between plasma and semen levels. Semen levels could be significantly greater for therapeutic doses of more than 100 mg/day. Since the threshold dose for birth defects and thalidomide exposure is not known, male patients are advised to use barrier contraception.
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In vivo evaluation of 111In-DTPA-N-TIMP-2 in Kaposi sarcoma associated with HIV infection. EUROPEAN JOURNAL OF NUCLEAR MEDICINE 2001; 28:756-61. [PMID: 11440037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Matrix metalloproteinases are the major agents responsible for the degradation of extracellular matrix and are produced at high levels by transformed and tumour cells, where they participate in the metastatic process by allowing local invasion. They are also more active at sites of new normal growth and angiogenesis. In the early stages of Kaposi sarcoma (KS), in vitro studies have demonstrated that vascular invasion can be inhibited by inhibitors of matrix metalloproteinases. Imaging of visceral and cutaneous KS presents a problem and therefore the potential use of a labelled inhibitor of metalloproteinases, N-TIMP-2, with indium-111 was thought to present a possible imaging tool. The biokinetics, dosimetry and potential for imaging with 111In-DTPA-N-TIMP-2 were assessed in five patients with HIV infection and KS. Between 103.1 and 108.0 MBq of this agent was injected into each patient, and the dynamic uptake over the kidneys was assessed, whole body scans were performed and blood samples were obtained. The clearance from the blood was rapid, with a first component half-time of 16.6+/-3.4 min and a second component half-time of 9.68+/-2.68 h. Two out of five patients experienced minor shivering but one of these patients was generally unwell before the study. The last three patients had no such problems. The tracer distributed predominantly to the kidneys and did not localise in other tissues. No KS lesions were clearly identified. 111In-DTPA-N-TIMP-2 can be successfully prepared and administered to patients safely, with a biodistribution and dosimetry which would allow its use as an imaging tracer. It is unlikely to be of use for imaging KS, but may have a role in other tumours that produce matrix metalloproteinases.
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The relationships between ethnicity, sex, risk group, and virus load in human immunodeficiency virus type 1 antiretroviral-naive patients. J Infect Dis 2001; 183:1518-21. [PMID: 11319688 DOI: 10.1086/320191] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2000] [Revised: 02/14/2001] [Indexed: 11/03/2022] Open
Abstract
This cross-sectional study examined the relationships between ethnicity, sex, risk group, and virus load in human immunodeficiency virus type 1 (HIV-1) antiretroviral-naive patients. HIV-1 RNA levels were measured in 322 patients attending St. Thomas' Hospital between May 1997 and February 1999. By univariate analyses, only clinical status and CD4(+) cell count were related to virus load. In multivariate analysis, variables independently related to virus load were CD4(+) cell count (P=.001), being black African (P=.001), having a nonsexual risk for HIV infection (P=.03), and having AIDS (P=.05). Neither sex nor age was a significant predictor of initial virus load after adjusting for other variables. For a given CD4(+) cell count, black Africans and people who contracted HIV nonsexually presented with a virus load lower than that of patients in other groups. Because virus loads may need to be interpreted differently according to ethnicity, this may affect decisions on when to initiate antiretroviral therapy and how to interpret clinical trial results.
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Highly active antiretroviral therapy normalizes the potential for MIP-1alpha production in HIV infection. J Infect 2000; 41:252-5. [PMID: 11120614 DOI: 10.1053/jinf.2000.0742] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
DESIGN The CC chemokines RANTES, MIP-1alpha and MIP-1beta are ligands for CCR5, which has been identified as the principal co-receptor for macrophage tropic strains of HIV-1. This study investigated whether the inducible levels of RANTES, MIP-1alpha and MIP-1beta produced by cultured whole blood samples related to different rates of progression of HIV infection and to the introduction of Nelfinavir-based highly active anti-retroviral therapy (HAART). METHODS Study subjects were HIV-positive and categorized as "slow progressors" (n= 8) or as "fast progressors" (n= 7); the latter group were treated with HAART. MIP-1alpha, MIP-1beta and RANTES production was determined using commercial ELISA kits. RESULTS The inducible production of MIP-1alpha by whole blood cells in culture was significantly depressed in patients starting therapy compared with "slow progressors" and "normal donors". The levels of MIP-1alpha significantly increased with therapy at 12 weeks compared with pre-HAART levels (P= O.05) and became comparable to that of "normals" and "slow progressors". Differences in the inducible levels of MIP-1beta and RANTES for the separate subject groups were not significant. CONCLUSIONS The increase in inducible MIP-1alpha production following HAART might suggest a role for the chemokines in HIV disease, either for monitoring the outcome of therapy of HIV disease, or as a direct therapeutic intervention.
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Abstract
New combinations of antiretrovirals have improved the quality of life and length of survival of patients with HIV infection and AIDS, but they have significant disadvantages. These include considerable toxicity, the development of drug resistance and expense. Successful immunotherapeutic vaccination against HIV would overcome these problems. None of the approaches that have been tried so far have shown a sufficient effect on HIV replication or on immunorestoration to merit their introduction to clinical practice. The most developed agent thus far is Remune, a gp120 depleted whole killed HIV-1 vaccine that has shown marked cytotoxic T lymphocyte responses when administered to man. CD4 count and HIV-1 viral load responses have occurred, but have so far been disappointing in their magnitude. Remune is entering Phase III trials in North America, Europe and the Far East, to determine clinical efficacy. Immunization using recombinant HIV envelope proteins, such as rgp160, for example with VaxSyn, have failed to produce a therapeutic response. Similarly, agents using HIV core antigens, such as p24VLP, have also failed to work. Hence, newer strategies have been tried. Recombinant canarypox vaccines like ALVAC 1452 and highly attenuated vaccinia virus vaccines, such as NYVAC, have been used in combination with HIV genes and peptides. Preliminary results suggest that they might reduce the HIV replication rate, but this needs confirming in larger clinical trials. DNA vaccination has produced encouraging results in monkeys, but the success has not yet been repeated in humans. Other strategies at an early stage include the exploitation of the protective alloimmune response in man. Outside the immunotherapeutic area, other promising new strategies that are being developed in parallel, include the fusion inhibitors, such as T-20. The potential benefits from a successful immunotherapeutic vaccine dictate that this area should, and will receive priority.
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Serologic evidence of human herpesvirus 8 transmission by homosexual but not heterosexual sex. J Infect Dis 1999; 180:600-6. [PMID: 10438345 DOI: 10.1086/314926] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Epidemiologic studies link Kaposi's sarcoma with a sexually transmitted agent. Human herpesvirus 8 (HHV-8) is likely to be that agent, but routes of transmission are poorly described. A seroepidemiologic study was conducted to determine whether HHV-8 is transmitted sexually between heterosexuals. Sera from 2718 patients attending a sexually transmitted disease (STD) clinic were tested for antibodies to HHV-8 and herpes simplex virus type 2 (HSV-2). Information on sex partners in the previous 12 months and past STDs were obtained by questionnaire. Relationships between possible risk factors and HHV-8 infection were assessed by logistic regression. Overall, seroprevalence of HHV-8 was 7.3%. Independent risk factors for HHV-8 in the whole group were homo/bisexuality and birth in Africa and, among homo/bisexual men, a history of syphilis and HSV-2 and human immunodeficiency virus seropositivity. Among heterosexuals there was no evidence for sexual transmission; the only independent risk factor for HHV-8 seropositivity was birth in Africa.
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Controlled management of public relations following a public health incident. JOURNAL OF PUBLIC HEALTH MEDICINE 1999; 21:251-4. [PMID: 10528951 DOI: 10.1093/pubmed/21.3.251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
This paper describes the management of public relations following an outbreak of multidrug resistant TB at a London hospital. Eight patients were involved, all of the secondary cases occurred in HIV seropositive patients, and three cases died. The paper describes how the the Incident Committee undertook to recall contacts of the cases for screening, inform the general practitioners of all of the contacts about their patients' exposure, warn other organizations and professionals interested or involved in the management of HIV in the London area as to the nature of the incident, and establish a helpline, before informing a wider audience through the EPINET, Communicable Disease Report and national press.
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Abstract
We aim to assess the usefulness of the cytomegalovirus (CMV) pp65 antigenaemia test, also called the CMV direct antigen test (DAT), in the management of patients with advanced human immunodeficiency virus (HIV) infection; we studied all patients who had pp65 assays between 8 September 1995 and 30 August 1996. Twenty-three patients had 31 tests. The mean CD4 cell count was 20/mm3. The tests were negative in 16 patients, of whom 12 have not developed CMV end-organ disease after a mean follow up of 114 days (range 14-269 days), whilst the remaining 4 patients had previously treated CMV disease. Eleven patients had positive tests: 4 had active CMV disease, 2 subsequently developed CMV retinitis, 2 died within a fortnight of multi-drug resistant tuberculosis (MDR-TB), one was lost to follow up and 2 have remained disease-free. This test has a positive predictive value of 43% and a negative predictive value of 94%, Fisher's exact test P=0.03. The pp65 antigenaemia assay can be performed in a standard virology laboratory avoiding the problems associated with polymerase chain reaction (PCR), a result is available within 5 h, and it is semi-quantifiable. However, a large prospective study is required to determine the comparative value and roles of the pp65 antigenaemia assay and DNA PCR in the management of CMV disease, especially with regard to the use of primary prophylaxis and pre-emptive therapy.
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Abstract
We describe the epidemiology and control of a hospital outbreak of multi-drug-resistant tuberculosis (MDR-TB). A human immunodeficiency virus (HIV)-negative patient with drug-sensitive tuberculosis developed MDR-TB during a period of unsupervised therapy. She was admitted to an isolation room in a ward with HIV-positive patients, but the room, unbeknown to hospital staff, was at positive-pressure relative to the main ward. Seven HIV-positive contacts developed MDR-TB. The diagnosis in the second patient was delayed, partly because acid-fast bacilli in his sputum were assumed to be Mycobacterium avium-intracellulare. All the available Mycobacterium tuberculosis isolates were indistinguishable by molecular typing. Nearly 1400 staff and patient contacts were offered screening, but the screening programme detected only one of the cases. Despite therapy, the index patient and two of the contacts died. HIV-positive patients are more likely than others to develop tuberculosis after exposure, and the disease may progress more rapidly. In these patients the possibility that acid-fast bacilli may represent M. tuberculosis must always be considered. Patients with tuberculosis (suspected or proven) should not be nursed in the same wards as immunosuppressed patients, and should be isolated. MDR-TB cases must be isolated in negative-pressure rooms. Hospital side-rooms may be positive-pressure as a fire safety measure; infection control teams must be aware of the airflows in all isolation rooms, and must be consulted during the design of hospital buildings. Good communication between infection control teams and clinicians is important, and all medical and nursing staff must be aware of the principles of management of patients with proven or suspected tuberculosis and MDR-TB.
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MESH Headings
- Acquired Immunodeficiency Syndrome/complications
- Acquired Immunodeficiency Syndrome/drug therapy
- Acquired Immunodeficiency Syndrome/virology
- Antiviral Agents/therapeutic use
- CD4 Lymphocyte Count
- DNA, Viral/analysis
- Female
- HIV/drug effects
- HIV/genetics
- Humans
- Lymphoma, AIDS-Related/complications
- Lymphoma, AIDS-Related/drug therapy
- Lymphoma, AIDS-Related/immunology
- Lymphoma, Non-Hodgkin/complications
- Lymphoma, Non-Hodgkin/drug therapy
- Lymphoma, Non-Hodgkin/immunology
- Male
- Neoplasms/complications
- Neoplasms/drug therapy
- Neoplasms/immunology
- Sarcoma, Kaposi/complications
- Sarcoma, Kaposi/drug therapy
- Sarcoma, Kaposi/immunology
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A pilot phase II study of the safety and immunogenicity of HIV p17/p24:VLP (p24-VLP) in asymptomatic HIV seropositive subjects. J Infect 1997; 35:231-5. [PMID: 9459393 DOI: 10.1016/s0163-4453(97)92814-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The aim of this phase II study was to evaluate the safety, immunogenicity and tolerability of the yeast-derived virus-like particle immunogen, Ty.p24.VLP (p24-VLP), in HIV-antibody-positive asymptomatic volunteers. Fifteen informed and consented volunteers, with p24 Antibody titres >1/100, p24 Antigen <20 pg/l, and CD4>350 x 10(9)/l were enrolled. Five were immunized with aluminium hydroxide placebo, five with 25 microg, and five with 100 microg p24-VLP in Alum adjuvant at weeks 0 and 4 by the intramuscular route. Patients were followed for 16 weeks post vaccination and the main outcome assessments were CD4 and CD8 lymphocyte counts, p24 antigen and antibody, Ty antibody and quantitative viral cultures. No serious adverse events were observed in any of the groups. There were increases in CD4 counts in the treated groups but not in the controls, although these changes were not statistically significant. There were no significant intrasubject or intergroup changes in the other parameters, such as p24 antigen and antibody. No pattern of change in plasma viraemia was detected, and most cultures were negative. Therefore we conclude that p24-VLP immunizations of 25 microg and 100 microg are well tolerated, and the CD4 changes are encouraging, but higher doses and larger numbers are required to see if there are significant humoral or cellular responses, and extended phase II studies are now in progress.
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Abstract
AIDS-associated Kaposi's sarcoma (KS) is much more frequent in patients acquiring HIV infection via the sexual route. Epidemiological studies have confirmed the likely involvement of a sexually acquired cofactor in the pathogenesis of this form of KS. We have formulated a set of postulates, epidemiological and experimental, to fit a single unifying hypothetical agent. Chlamydia trachomatis is one of 3 agents to fit the epidemiological criteria. Our data suggest a possible association between increased IgG serum antibody to C. trachomatis and the occurrence of KS. Conversely, higher titres of IgG serum antibody to C. pneumoniae were associated with the absence of KS. We feel that it is important to study further the relationship between C. trachomatis and KS.
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Abstract
Pneumocystis carinii pneumonia (PCP) is one of the most common AIDS-defining diagnoses. First-line therapy is cotrimoxazole (trimethoprim-sulfamethoxazole), despite a high incidence of toxic effects, and a greater incidence of hypersensitivity reactions among HIV-positive patients compared with the seronegative population. Alternative agents such as intravenous pentamidine, or clindamycin with primaquine, and trimethoprim with dapsone, also have a wide range of serious adverse effects, but remain treatment options. Atovaquone appears promising for the treatment of both PCP and toxoplasmosis, and has a lower reported incidence of toxicity than the alternative agents. The most toxic antifungal drugs are reserved for serious infections, such as cryptococcal meningitis. Liposomal amphotericin B has less renal toxicity than standard formulations, and exemplifies that new formulations of existing drugs, although often expensive, may have a better adverse effect profile. There are 2 different drugs currently available for cytomegalovirus (CMV) infections, ganciclovir and foscarnet. Both have a high incidence of serious adverse effects; ganciclovir mainly causes bone marrow toxicity and foscarnet leads to renal toxicity. The drugs used for mycobacterial infection (including mycobacteria as well as tuberculosis) have a wide range of adverse effects, particularly skin rashes and drug-induced hepatitis. Some of these compounds are quite new, such as rifabutin and clarithromycin, and it is important to be ever vigilant for previously unreported adverse effects.
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Mitochondrial myopathy associated with chronic zidovudine therapy in AIDS. THE QUARTERLY JOURNAL OF MEDICINE 1993; 86:5-15. [PMID: 8438050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
One hundred and eighteen consecutively identified AIDS patients, 88 of whom received zidovudine (1000-1200 mg/day), were followed for 1 year to investigate prospectively the relationship between zidovudine and myopathy. Clinical and biochemical evidence of proximal myopathy was seen in 7 of 41 patients (17%) who had been receiving zidovudine for more than 270 days, but in none of those on short-term therapy and in none of the controls. Serum creatine kinase levels rose a mean of 76 days (range 34-187) before the onset of clinical signs. Creatine kinase returned to normal within 4 weeks of cessation of zidovudine and strength returned within 8 weeks, though loss of muscle bulk persisted. Chronic malaise, anorexia and nausea accompanied the myopathy and remitted within 8 weeks of stopping zidovudine. Muscle histology in four patients with myopathy showed fibre size variation with atrophic, necrotic and degenerating fibres and an absence of inflammation. Ultrastructural studies showed glycogen-packed sarcoplasm, lipid droplets and grossly giant mitochondria. These abnormalities improved substantially after stopping zidovudine. Similar but less marked changes were seen in a zidovudine treated patient without myopathy, but were absent in one AIDS patient not taking the drug. Long-term zidovudine therapy is associated with a mitochondrial myopathy and the constitutional features suggest that it is part of a wider disorder affecting cellular function in other tissues.
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Cavitating pulmonary cryptococcosis developing in an HIV antibody patient despite prior treatment with fluconazole. Genitourin Med 1992; 68:42-4. [PMID: 1548011 PMCID: PMC1194797 DOI: 10.1136/sti.68.1.42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Disseminated cryptococcosis developed in an HIV antibody positive patient who was taking fluconazole for oral candidiasis. This case highlights the poor response to therapy that may be seen, and the severe pulmonary complications that may ensue. The use of fluconazole prior to the development of cryptococcosis did not confer protection.
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Clinical care and management. AIDS Care 1991; 3:457-60. [PMID: 1786283 DOI: 10.1080/09540129108251609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Abstract
Among 347 AIDS patients seen at St Mary's Hospital, London between 1983 and 1989, cytomegalovirus (CMV) disease was observed in 75 (22%). Of these, 58 (77%) had CMV retinitis, 26 (35%) CMV colitis, and 12 (16%) had CMV infection diagnosed at other sites. Relapse occurred in 71%. A favourable response to the use of ganciclovir as induction therapy for CMV retinitis was observed in 92%. Relapse of CMV retinitis occurred in 54% at a median time of 97 days. Neutropenia was the most frequent and serious side-effect of ganciclovir, 76% patients having neutrophil counts less than 1.0 x 10(9)/l and 48% less than 0.5 x 10(9)/l at some stage of therapy. Thrombocytopenia was also common, and platelet counts of less than 50 x 10(9)/l occurred in 43% patients on ganciclovir. The concurrent use of zidovudine made the development of severe neutropenia and thrombocytopenia more likely. Median survival following the diagnosis of CMV disease increased from 5-8 months between 1984 and 1987, to over 12 months in 1988. Patients with CMV colitis had a worse prognosis than patients with CMV retinitis, with median survival of 4.5 and 7 months respectively. In conclusion, CMV is an important opportunist infection in AIDS and both the disease and its treatment cause considerable morbidity. Hence, it is important to develop more effective and less toxic forms of therapy for CMV infection.
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Abstract
Disseminated Strongyloides stercoralis infection is a rare and severe but treatable complication of AIDS. We present a case where this infection was successfully treated and review the available literature. Cases may present many years after they have left an area endemic for Strongyloides infection, emphasizing the need for a full travel history. Symptoms are typically gastrointestinal and pulmonary, with infiltrates often seen on chest radiography. Diagnosis requires stool examination and biopsy of affected sites. Treatment with repeated courses of thiabendazole (25 mg/kg twice daily for 5 days) was successful in our case, but maintenance regimens have not yet been defined. The relative rarity of this complication of AIDS suggests that, where both infections are present, disseminated strongyloidiasis only arises either when HIV-induced immunodeficiency is profound or, possibly, when it is accompanied by impaired granulopoiesis.
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Changing disease patterns in AIDS. Nurs Stand 1991; 5:16. [PMID: 1900997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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AIDS profile has changed. NURSING TIMES 1991; 87:10. [PMID: 1996233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Changing disease patterns in patients with AIDS in a referral centre in the United Kingdom: the changing face of AIDS. BMJ (CLINICAL RESEARCH ED.) 1991; 302:203-7. [PMID: 1998759 PMCID: PMC1669078 DOI: 10.1136/bmj.302.6770.203] [Citation(s) in RCA: 127] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To study the changes in morbidity, mortality, and survival patterns in a population of patients with AIDS in the United Kingdom from 1982 to 1989. DESIGN A retrospective analysis of inpatient and outpatient records of patients with AIDS. SUBJECTS 347 Patients with AIDS, predominantly homosexual or bisexual men. SETTING Departments of immunology and genitourinary medicine, St Mary's Hospital, London. MAIN OUTCOME MEASURES Presenting diagnosis of AIDS, occurrence of other opportunist diseases, cause of death, and survival since AIDS was diagnosed, in particular for those patients with Pneumocystis carinii pneumonia or Kaposi's sarcoma. RESULTS The overall proportion of patients who developed P carinii pneumonia dropped from 56% (20/36) in 1984 to 24% (46/194) in 1989, although it has remained the index diagnosis in about half of new patients. Kaposi's sarcoma has decreased as index diagnosis from 30% (20/67) to 20% (15/74) over the same period, though the prevalence has remained constant at around 35%. P carinii pneumonia accounted for 46% (16/35) of known causes of death in 1986 but only 3% (1/31) in 1989. Conversely, deaths due to Kaposi's sarcoma rose from 14% (1/7) to 32% (10/31) between 1984 and 1989. Lymphoma accounted for an increased proportion of deaths among these patients with 16% (5/31) of deaths in 1989. Their median survival increased from 10 months in 1984-6 to 20 months in 1987. CONCLUSIONS The changing patterns of disease in patients with AIDS have important implications both for health care provision and future medical research. Medical and nursing provision must be made for the increased morbidity of these diseases and the increased survival of these patients. Research should now be directed towards developing effective treatments for the opportunist infections which are currently more difficult to treat, the secondary malignancies of AIDS, as well as more effective immunorestorative treatments. Future changes in disease patterns must be recognised at an early stage so that resources can be adequately planned and allocated.
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Visceral leishmaniasis in HIV infection and AIDS: clinical features and response to therapy. THE QUARTERLY JOURNAL OF MEDICINE 1990; 77:1101-11. [PMID: 2274656 DOI: 10.1093/qjmed/77.2.1101] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The development of visceral leishmaniasis with atypical features in an AIDS patient, and the recent flurry of reports of visceral leishmaniasis in HIV-infected individuals prompted the review of its manifestations in the 47 reported cases. Splenomegaly, which is almost always a feature of visceral leishmaniasis in the immunocompetent host, was absent in eight. Antibodies to Leishmania donovani, which are present in approximately 95 per cent of immunocompetent patients with visceral leishmaniasis, were absent in 29 of 45 (66 per cent) of HIV-infected patients tested. Nine HIV-positive patients with visceral leishmaniasis did not exhibit a primary clinical response to therapy with antimonials and of those who did show a response, relapse occurred in 13, at a mean 4.5 months after stopping therapy. Seventeen patients are known to have died often in association with respiratory disease; Leishmania was seen in one bronchial lavage specimen and in lung tissue in one post-mortem performed. In order to improve the prognosis of visceral leishmaniasis in HIV-infected patients diagnosis will have to be made earlier, taking account of the atypical features, and treatment will need to be improved, both initially and perhaps also by the use of long-term maintenance therapy.
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How are resistant strains of Staphylococcus aureus acquired in the community? SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 1990; 22:761-2. [PMID: 2284586 DOI: 10.3109/00365549009027139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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