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1.
Vox Sang ; 113(1): 3-12, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29193128

ABSTRACT

Transfusion-transmitted infection risk remains an enduring challenge to blood safety in Africa. A high background incidence and prevalence of the major transfusion-transmitted infections (TTIs), dependence on high-risk donors to meet demand, suboptimal testing and quality assurance collectively contribute to the increased risk. With few exceptions, donor testing is confined to serological evaluation of human immunodeficiency virus (HIV), hepatitis B and C (HBV and HCV) and syphilis. Barriers to implementation of broader molecular methods include cost, limited infrastructure and lack of technical expertise. Pathogen reduction (PR), a term used to describe a variety of methods (e.g. solvent detergent treatment or photochemical activation) that may be applied to blood following collection, offers the means to diminish the infectious potential of multiple pathogens simultaneously. This is effective against different classes of pathogen, including the major TTIs where laboratory screening is already implemented (e.g. HIV, HBV and HCV) as well pathogens that are widely endemic yet remain unaddressed (e.g. malaria, bacterial contamination). We sought to review the available and emerging PR techniques and their potential application to resource-constrained parts of Africa, focusing on the advantages and disadvantages of such technologies. PR has been slow to be adopted even in high-income countries, primarily given the high costs of use. Logistical considerations, particularly in low-resourced parts of Africa, also raise concerns about practicality. Nonetheless, PR offers a rational, innovative strategy to contend with TTIs; technologies in development may well present a viable complement or even alternative to targeted screening in the future.


Subject(s)
Blood Safety/methods , Africa , Blood Donors , Blood Safety/economics , Blood Transfusion/standards , Communicable Disease Control , Communicable Diseases/transmission , Developing Countries , Health Resources , Hepatitis C/blood , Humans , Risk Reduction Behavior
2.
J Econ Entomol ; 110(3): 954-960, 2017 06 01.
Article in English | MEDLINE | ID: mdl-28444314

ABSTRACT

The avocado industry is important in South Africa, but access to certain markets is impeded by the presence of phytosanitary pests. One of the ways of securing entry to these markets is to demonstrate that a mitigating treatment will result in there being a negligible chance of accidental importation. In cold treatment comparative studies at 0 °C and 2 °C of immature stages of Ceratitis capitata (Wiedemann), Ceratitis rosa Karsch, and Ceratitis cosyra (Walker) in "Hass" avocado, the third instar of C. cosyra was shown to be the most cold tolerant. This larval life stage was used in a large-scale trial to test treatment efficacy at 2 °C, a temperature known to be the better for fruit quality. There were no survivors from the 49,795 individual fruit fly larvae subjected to the cold treatment at 2 °C for 20 d. It is argued that, although this level of assessment falls short of the Probit 9 level normally required for fruit fly, they are rarely found in avocado fruit and that the level of disinfestation obtained is more than sufficient to achieve quarantine security.


Subject(s)
Cold Temperature/adverse effects , Insect Control/methods , Persea , Quarantine/methods , Tephritidae/physiology , Animals , Ceratitis capitata/growth & development , Ceratitis capitata/physiology , Fruit , Larva/growth & development , Larva/physiology , Species Specificity , Tephritidae/growth & development
3.
J Econ Entomol ; 109(5): 2238-42, 2016 10.
Article in English | MEDLINE | ID: mdl-27567224

ABSTRACT

Some countries consider false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), a phytosanitary pest and may require the application of a mitigation treatment before accepting T. leucotreta-susceptible produce. This research reports on cold treatments that provide the phytosanitary security that this pest would not be accidentally imported alive. More than 35,000 individuals were treated for 20 d at 0.8 °C and >30,000 individuals subjected to - 0.6 °C for 18 d, with no survivors. The adoption of these treatments in international fruit trade protocols is recommended.


Subject(s)
Cold Temperature , Moths/physiology , Pest Control, Biological/methods , Vitis , Animals , Fruit , Larva/growth & development , Larva/physiology , Moths/growth & development
4.
J Econ Entomol ; 105(6): 1963-70, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23356059

ABSTRACT

Bactrocera invadens (Diptera: Tephritidae) has spread rapidly across Africa and currently poses a phytosanitary threat to the fruit industry of South Africa. In reaction a cold mitigating treatment to provide phytosanitary security to importing countries was developed in Nairobi, Kenya. Using laboratory reared fruit flies, the rate of development in 'Hass' avocado (Persea americana Miller) was determined at 28 degrees C. Fruit ripeness or softness was found to be a factor improving larval fruit fly survival. Using this information the egg and larval developmental stages were subjected to 2 degrees C cold treatment and it was found that the third instars were the most cold tolerant life stage and that it was expected that between 16 and 17 d treatment would provide phytosanitary security. There were no survivors in the treatment of an estimated 153,001 individuals in four replicates at an average fruit pulp temperature of 2 degrees C satisfying the Probit 9 level of efficiency at a confidence of >95%. These data provide evidence that a continuous cold treatment of 1.5 degrees C or lower for 18 d would provide phytosanitary security in that any consignment entering an importing country poses no risk of accidental importation of B. invadens.


Subject(s)
Cold Temperature , Insect Control , Persea/parasitology , Tephritidae/growth & development , Animals , Food Parasitology , Fruit/parasitology , Larva/growth & development
5.
Lupus ; 15(4): 198-206, 2006.
Article in English | MEDLINE | ID: mdl-16686258

ABSTRACT

The objective of this study was to determine the medical outcomes including the ovarian function childhood-onset SLE (cSLE). The medical records of all patients diagnosed with cSLE in the Greater Cincinnati area between 1981 and 2002 were reviewed. Patient interviews were performed to obtain additional information on current medication regimens, disease activity [SLE Disease Activity Index (SLEDAI-2k)], and damage [Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI)]. The occurence of premature ovarian failure (POF) and reduction of the ovarian reserve was assessed by timed gonadotropin levels. There were 77 patients (F : M = 70 : 7, 53% Caucasian, 45% African-American and 2% Asian) with a mean age at diagnosis of 14.6 years. Nine patients died (88.3% survival) during the mean follow-up of 7.1 years (standard deviation [SD] 5.6) and 88% of the patients continued to have active disease (SLEDAI-2k mean/SD: 6.6/6.7), with 42% of them having disease damage (SDI mean/SD: 1.62/2.1); Non-Caucasian patients had higher disease activity (mean SLEDAI-2k: 10 versus 3.4; P < 0.0001) and more disease damage (mean SDI : 2.1 versus 1.2; P < 0.02) than Caucasian patients. Cyclophosphamide was given to 47% of the patients during the course of their disease and associated with the presence of significantly reduced ovarian reserve (RR = 2.8; 95% CI: 1.7-4.8; P = 0.026). Patient mortality and disease damage with cSLE continue to be high. Although overt POF with cyclophosphamide exposure is rare, it is a risk factor for significantly decreased ovarian reserve cSLE.


Subject(s)
Cyclophosphamide/adverse effects , Immunosuppressive Agents/adverse effects , Lupus Erythematosus, Systemic/drug therapy , Primary Ovarian Insufficiency/chemically induced , Adolescent , Child , Child, Preschool , Female , Humans , Lupus Erythematosus, Systemic/mortality , Lupus Erythematosus, Systemic/pathology , Male , Ovary/drug effects , Testis/drug effects
6.
Br J Sports Med ; 40(7): 605-9, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16611724

ABSTRACT

BACKGROUND: There is concern about whether cardiac damage occurs as a result of prolonged strenuous exercise. OBJECTIVE: To investigate whether competing in a triathlon is associated with cardiac damage based on a sustained increase in cardiac troponin T (cTnT), and whether such an increase correlates with echocardiographic changes METHODS: cTnT and echocardiographic measurements were made in 38 participants in the 2001 Australian ironman triathlon. cTnT was measured the day before, immediately after, and the day following the race. Echocardiography was done the day before, immediately after, and two to six weeks later for measurement of ejection fraction, stroke volume, cardiac output, wall motion analysis, and global left ventricular function (LVF). RESULTS: No subject had detectable cTnT in the pre-race sample. Following the race, 32 subjects (86.5%) had detectable levels of cTnT (>0.01 ng/ml), with six (16.2%) having >0.10 ng/ml. The day after the race, nine subjects (23.7%) still had detectable cTnT, with two recording a level >0.10 ng/ml. Previously described echocardiographic changes of "cardiac fatigue" were observed in the whole cohort. There was a modest but significant correlation between change in ejection fraction and peak cTnT level (p = 0.02, r = 0.39). Athletes with a post-race cTnT >0.10 ng/ml had a greater decrease in global LVF (p = 0.02) and a trend toward a greater fall in ejection fraction and stroke volume than athletes with cTnT levels <0.10 ng/ml. Cardiac output fell in the group with cTnT >0.10 ng/ml (p>0.05). CONCLUSIONS: Participation in ironman triathlon often resulted in persistently raised cTnT levels, and the troponin rise was associated with echocardiographic evidence of abnormal left ventricular function. The clinical significance and long term sequelae of such damage remains to be determined.


Subject(s)
Bicycling/physiology , Running/physiology , Swimming/physiology , Troponin T/metabolism , Ventricular Dysfunction, Left/diagnostic imaging , Adult , Australia , Cardiac Output/physiology , Echocardiography , Female , Humans , Male , Physical Endurance/physiology , Stroke Volume/physiology , Ventricular Dysfunction, Left/metabolism
7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(6 Pt 2): 067402, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15697563

ABSTRACT

The link between the development of sheared flows and the structure of turbulence has been investigated in the plasma boundary region of the TJ-II stellarator. The development of the naturally occurring velocity shear layer requires a minimum plasma density. Near this critical density, the level of edge turbulent transport and the turbulent kinetic energy significantly increases in the plasma edge. The resulting shearing rate in the phase velocity of fluctuations is comparable to the one required to trigger a transition to improved confinement regimes with reduction of edge turbulence, suggesting that spontaneous sheared flows and fluctuations keep themselves near marginal stability. These findings provide the experimental evidence of coupling between sheared flows development and increasing in the level of edge turbulence. The experimental results are consistent with the expectations of second-order transition models of turbulence-driven sheared flows.

8.
Phys Rev Lett ; 89(12): 125003, 2002 Sep 16.
Article in English | MEDLINE | ID: mdl-12225090

ABSTRACT

Compact stellarator configurations have been obtained with good neoclassical confinement that are stable to both pressure- and current-driven modes for high values of beta. These configurations are drift-optimized tokamak-stellarator hybrids with a high-shear tokamak-like rotational transform profile and /B/ that is approximately poloidally symmetric. The bootstrap current is consistent with the required equilibrium current and, while larger than that in existing stellarators, is typically only a small fraction (1/3-1/5) of that in an equivalent tokamak. These configurations have strong magnetic wells and consequently high interchange stability beta limits up to beta=23%. Because of the reduced bootstrap current, these configurations are stable to low-n ideal MHD kink modes with no wall stabilization for values of beta ( approximately 7%-11%) significantly larger than in an equivalent advanced tokamak.

9.
Bull World Health Organ ; 80(5): 342-9, 2002.
Article in English | MEDLINE | ID: mdl-12077608

ABSTRACT

OBJECTIVE: To assess the sensitivity, specificity and predictive value positive of the WHO threshold strategy for detecting meningococcal disease epidemics in sub-Saharan Africa and to estimate the impact of the strategy on an epidemic at district level. METHODS: Data on meningitis cases at the district level were collected weekly from health ministries, WHO country and regional offices, and nongovernmental organizations in countries where there were epidemics of meningococcal disease in 1997. An epidemic was defined as a cumulative district attack rate of at least 100 cases per 100,000 population from January to May, the period of epidemic risk. The sensitivity, specificity and predictive value positive of the WHO threshold rate were calculated, and curves of sensitivity against (1 - specificity) were compared with alternatively defined threshold rates and epidemic sizes. The impact of the WHO strategy on a district epidemic was estimated by comparing the numbers of epidemic cases with cases estimated to have been prevented by vaccination. FINDINGS: An analysis was made of 48 198 cases reported in 174 districts in Benin, Burkina Faso, the Gambia, Ghana, Mali, Niger, and Togo. These cases were 80.3% of those reported from Africa to WHO during the 1997 epidemic period. District populations ranged from 10,298 to 573,908. The threshold rate was crossed during two consecutive weeks in 69 districts (39.7%) and there were epidemics in 66 districts (37.9%). Overall, the sensitivity of the threshold rate for predicting epidemics was 97%, the specificity was 95%, and the predictive value positive was 93%. Taken together, these values were equivalent or better than the sensitivity, specificity and predictive value positive of alternatively defined threshold rates and epidemics, and remained high regardless of district size. The estimated number of potential epidemic cases decreased by nearly 60% in the age group targeted for vaccination in one district where the guidelines were followed in a timely manner. CONCLUSION: The use of the WHO strategy was sensitive and specific for the early detection of meningococcal disease epidemics in countries of sub-Saharan Africa during 1997 and had a substantial impact on a district epidemic. Nevertheless, the burden of meningococcal disease in these countries remains formidable and additional control measures are needed.


Subject(s)
Disease Outbreaks/prevention & control , Meningococcal Infections/epidemiology , Africa South of the Sahara/epidemiology , Disease Notification , Humans , Meningococcal Infections/diagnosis , Meningococcal Infections/prevention & control , Population Surveillance/methods , Sensitivity and Specificity , World Health Organization
12.
Foot Ankle Int ; 22(10): 832-5, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11642536

ABSTRACT

The distal chevron osteotomy is a well-established technique for correction of symptomatic mild to moderate metatarsus primus varus with hallux valgus deformity. Fixation of the osteotomy ranges from none to bone pegs, Kirschner wires, screws, or absorbable pins. We evaluated one surgeon's (J.K.D.) results of distal chevron osteotomy fixation with a single, nonpredrilled, 1.3-mm poly-p-dioxanone pin and analyzed any differences in patients with unilateral or bilateral symptomatic metatarsus primus varus with hallux valgus deformities. All osteotomies healed without evidence of infection, osteolysis, nonunion, or necrosis. Equal correction was achieved in unilateral and bilateral procedures. The technique is quick and easy, and adequate fixation is achieved.


Subject(s)
Bone Nails , Hallux Valgus/surgery , Osteotomy/methods , Polydioxanone , Adult , Aged , Aged, 80 and over , Follow-Up Studies , Hallux Valgus/diagnostic imaging , Humans , Middle Aged , Radiography , Time Factors
13.
Clin Infect Dis ; 32(7): E122-3, 2001 Apr 01.
Article in English | MEDLINE | ID: mdl-11264051

ABSTRACT

We present what is, to our knowledge, the second case report of a patient with acquired immunodeficiency syndrome and transfusion-dependent anemia caused by persistent infection with parvovirus B19. The patient's anemia was successfully treated, and she demonstrated serologic evidence of eradication of parvovirus after having received effective therapy for human immunodeficiency virus infection.


Subject(s)
AIDS-Related Opportunistic Infections/drug therapy , Parvoviridae Infections/drug therapy , Parvovirus B19, Human , AIDS-Related Opportunistic Infections/immunology , AIDS-Related Opportunistic Infections/virology , Adult , Anti-HIV Agents/therapeutic use , Antiretroviral Therapy, Highly Active , Chronic Disease , Didanosine/therapeutic use , Female , HIV Protease Inhibitors/therapeutic use , Humans , Nelfinavir/therapeutic use , Nevirapine/therapeutic use , Parvoviridae Infections/immunology , Parvoviridae Infections/virology , Parvovirus B19, Human/immunology , Parvovirus B19, Human/isolation & purification , Reverse Transcriptase Inhibitors/therapeutic use , Treatment Outcome
15.
J Infect ; 40(3): 274-81, 2000 May.
Article in English | MEDLINE | ID: mdl-10908023

ABSTRACT

OBJECTIVE: To determine the utility of brain thallium-201 single photon emission computerized tomography (Tl-201 SPECT) combined with Toxoplasma serology for the diagnosis of focal CNS lesions in patients with AIDS. METHODS: Sixty-one consecutive HIV-infected patients with focal CNS lesion(s) on head computed tomography (CT) or MRI scan who underwent brain Tl-201 SPECT and serum Toxoplasma serology were evaluated, retrospectively. Thallium-201 uptake ratios were calculated by comparing lesion activity to contralateral scalp activity. Diagnoses were made by a combination of histology, serology, PCR, and empirical response to therapy. Toxoplasma serologies (IgG IFA) were compared in the patients with central nervous system (CNS) toxoplasmosis and those without CNS toxoplasmosis. RESULTS: Fifty-six patients were evaluable and a definitive diagnosis was made in 38 patients: toxoplasmosis (17), lymphoma (14), PML (three), Aspergillus (one), tuberculoma (one), Cryptococcus (one), varicella-zoster virus (one). Patients with lymphoma had significantly higher lesion/contralateral scalp ratios compared to patients without lymphoma: 1.03 vs. 0.67, P < 0.05. Using a cut-off of 0.90 for the lesion/scalp uptake ratios (based on analysis of ROC curves) the sensitivity and specificity for the diagnosis of lymphoma were 86% and 83%, respectively. Serum Toxoplasma IgG titres were significantly higher in patients diagnosed with toxoplasmosis compared to those with a diagnosis other than toxoplasmosis, 1:5444 vs. 1:15, P < 0.05. Only one patient with confirmed toxoplasmosis had a Toxoplasma serology < 1:256, while no patients without toxoplasmosis (including all lymphoma patients) had serologies > 1:256. CONCLUSIONS: In a series of HIV-infected patients, Tl-201 SPECT was able to accurately differentiate primary brain lymphoma from other causes of focal CNS lesions in most patients; however, both false positive and false negative results occurred. By combining Tl-201 SPECT with serum Toxoplasma IgG, diagnostic accuracy was improved.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , Brain Neoplasms/diagnostic imaging , Thallium , Tomography, Emission-Computed, Single-Photon , Toxoplasmosis, Cerebral/blood , AIDS-Related Opportunistic Infections/blood , AIDS-Related Opportunistic Infections/parasitology , Adult , Animals , Antibodies, Protozoan/blood , Diagnosis, Differential , Female , Humans , Immunoglobulin G/blood , Lymphoma/diagnostic imaging , Male , Retrospective Studies , Serologic Tests , Toxoplasma/immunology , Toxoplasmosis, Cerebral/parasitology
16.
J Am Acad Dermatol ; 40(2 Pt 2): 350-5, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10025867

ABSTRACT

Sporotrichosis most commonly presents as a localized, lymphocutaneous infection that follows trauma, such as an injury from a rose thorn. In patients infected with HIV, it may be widespread and disseminated. We describe a patient with AIDS who developed disseminated sporotrichosis, a rare opportunistic fungal infection that may affect these patients. The condition remained undiagnosed because of failure to recognize characteristic histopathologic findings and failure of clinicians to interface closely with the microbiology laboratory. The condition was difficult to treat, requiring systemic administration of amphotericin. While localized sporotrichosis is an innocuous disorder that responds well to therapy, in immunocompromised hosts, it is potentially life-threatening and may require prolonged therapy with potentially toxic medications such as amphotericin B. It is important that clinicians be aware of the presentation of this unusual opportunistic infection and that they maintain close communication with pathology and clinical microbiology laboratories to ensure that proper stains and cultures are performed to avoid potential misdiagnosis.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , Sporotrichosis/diagnosis , AIDS-Related Opportunistic Infections/pathology , Adult , Biopsy , Diagnosis, Differential , Humans , Male , Patient Care Team , Skin/pathology , Sporothrix/ultrastructure , Sporotrichosis/pathology
17.
Cancer Pract ; 6(2): 107-13, 1998.
Article in English | MEDLINE | ID: mdl-9573910

ABSTRACT

PURPOSE: Prostate cancer occurs 37% more often in African-American men than in white men. Patients and their family care providers (FCPs) may have different experiences of cancer and its treatment. This report addresses two questions: 1) What is the relationship of uncertainty to family coping, psychological adjustment to illness, and spiritual factors? and 2) Are these patterns of relationship similar for patients and their family care givers and for whites and African-Americans? DESCRIPTION OF STUDY: A sample of white and African-American men and their family care givers (N = 403) was drawn from an ongoing study, testing the efficacy of an uncertainty management intervention with men with stage B prostate cancer. Data were collected at study entry, either 1 week after post-surgical catheter removal or at the beginning of primary radiation treatment. Measures of uncertainty, adult role behavior, problem solving, social support, importance of God in one's life, family coping, psychological adjustment to illness, and perceptions of health and illness met standard criteria for internal consistency. Analyses of baseline data using Pearson's product moment correlations were conducted to examine the relationships of person, disease, and contextual factors to uncertainty. RESULTS: For family coping, uncertainty was significantly and positively related to two domains in white family care providers only. In African-American and white family care providers, the more uncertainty experienced, the less positive they felt about treatment. Uncertainty for all care givers was related inversely to positive feelings about the patient recovering from the illness. For all patients and for white family members, uncertainty was related inversely to the quality of the domestic environment. For everyone, uncertainty was related inversely to psychological distress. Higher levels of uncertainty were related to a poorer social environment for African-American patients and for white family members. For white patients and their family members, higher levels of uncertainty were related to lower scores on adult role behavior (shopping, running errands). For white family members, higher levels of uncertainty were related to less active problem solving and less perceived social support. Finally, higher levels of uncertainty were related to the importance of God for white patients and family care providers. CLINICAL IMPLICATIONS: The clearest finding of the present study is that there are ethnic differences in the relationship of uncertainty to a number of quality-of-life and coping variables. This has immediate implications for the assessment of psychosocial responses to cancer and cancer treatment. Much of what is in curricula is based on clinical and research experience primarily with white individuals. The experience of uncertainty related to cancer and its treatment is influenced by the cultural perspectives of patients and their families. To assist patients and families with the inevitable uncertainties of the cancer experience, healthcare providers need to reconsider their ethnocentric assumptions and develop more skill in assessing patient and family beliefs, values, cultural perspectives, and the influence of these on patient and family uncertainties.


Subject(s)
Adaptation, Psychological , Black or African American/psychology , Family/ethnology , Fear , Prostatic Neoplasms/ethnology , Prostatic Neoplasms/psychology , White People/psychology , Aged , Humans , Male , Middle Aged , Religion and Psychology , Sick Role , Surveys and Questionnaires
19.
Plant Dis ; 82(12): 1323-1327, 1998 Dec.
Article in English | MEDLINE | ID: mdl-30845464

ABSTRACT

Preplant soil fumigation with methyl bromide at 49 and 98 g/m2 was compared with various postplant nematicide and fungicide programs in a replant citrus orchard infested with the citrus nematode Tylenchulus semipenetrans and the fungal pathogens Phytophthora nicotianae, Fusarium solani, and F. oxysporum. Postplant treatments comprised multiple applications of fenamiphos at 4.0 g a.i./m2 soil, aldicarb at 4.5 g a.i./m2 soil, metalaxyl at 4 g a.i./m2 soil, fose-tyl-Al stem painting at 400 g a.i./liter, and combinations of fenamiphos + fosetyl-Al and aldi-carb + fosetyl-Al at the same rates as for single treatments. P. nicotianae could not be detected in the entire experimental site after replanting, but populations of F. solani and F. oxysporum showed only a temporary decline following site preparation. T. semipenetrans did not re-establish in any of the treatments within the first 2 years. Numbers of juveniles remained low in most treatments during the third year, but thereafter both juveniles and females increased significantly in all except the fumigated plots. Female populations on roots of citrus trees planted in fumigated soil remained suppressed for 8 years and the trees developed more vigorously and produced higher yields and larger fruit than those in non-fumigated soil. Compared with the control, net income for the period 4 to 8 years after planting increased by 101 and 46% in plots fumigated with 49 and 98 g/m2, respectively. With the exception of aldicarb, all other treatments showed net losses.

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