Design and implementation of the Our Health Counts (OHC) methodology for First Nations, Inuit, and Metis (FNIM) health assessment and response in urban and related homelands

OBJECTIVES

Methods for enumeration and population-based health assessment for First Nations, Inuit, and Metis (FNIM) living in Canadian cities are underdeveloped, with resultant gaps in essential demographic, health, and health service access information. Our Health Counts (OHC) was designed to engage FNIM peoples in urban centres in "by community, for community" population health assessment and response.

METHODS

The OHC methodology was designed to advance Indigenous self-determination and FNIM data sovereignty in urban contexts through deliberate application of Indigenous principles and linked implementation strategies. Three interwoven principles (good relationships are foundational; research as gift exchange; and research as a vehicle for Indigenous community resurgence) provide the framework for linked implementation strategies which include actively building and maintaining relationships; meaningful Indigenous community guidance, leadership, and participation in all aspects of the project; transparent and equitable sharing of project resources and benefits; and technical innovations, including respondent-driven sampling, customized comprehensive health assessment surveys, and linkage to ICES data holdings to generate measures of health service use.

RESULTS

OHC has succeeded across six urban areas in Ontario to advance Indigenous data sovereignty and health assessment capacity; recruit and engage large population-representative cohorts of FNIM living in urban and related homelands; customize comprehensive health surveys and data linkages; generate previously unavailable population-based FNIM demographic, health, and social information; and translate results into enhanced policy, programming, and practice.

CONCLUSION

The OHC methodology has been demonstrated as effective, culturally relevant, and scalable across diverse Ontario cities.

Our Health Counts: Examining associations between colonialism and ever being incarcerated among First Nations, Inuit, and Métis people in London, Thunder Bay, and Toronto, Canada

OBJECTIVES

Indigenous peoples have a disproportionately high prevalence of incarceration in the Canadian justice system. However, there is limited Indigenous-driven research examining colonialism and the justice system, specifically associations between racism, externally imposed family disruptions, and history of ever being incarcerated. Therefore, this study examined the association between the proportion of previous incarceration and family disruption, experiences of racism, and victimization for Indigenous adults in London, Thunder Bay, and Toronto, Ontario, Canada. The three communities expressed that they did not want comparison between the communities; rather, they wanted analysis of their community to understand where more supports were needed.

METHODS

Indigenous community partners used respondent-driven sampling (RDS) to collect data from First Nations, Inuit, and Métis (FNIM) peoples in London, Thunder Bay, and Toronto. Prevalence estimates, 95% confidence intervals, and relative risk were reported using unweighted Poisson models and RDS-adjusted proportions.

RESULTS

Proportions of ever being incarcerated ranged from 43.0% in London to 54.0% in Toronto and 72.0% in Thunder Bay. In all three cities, history of child protection involvement and experiencing racism was associated with an approximate 25.0% increase in risk for previous incarceration. In Toronto and London, victimization was associated with increased risk for incarceration.

CONCLUSION

This research highlights disproportionately high prevalence of ever being incarcerated among FNIM living in three Ontario cities. Experiencing racism, family disruption, and victimization are associated with incarceration. Decreasing the rates of family disruption, experiences of racism, and victimization should inform future policy and services to reduce the disproportionately high prevalence of incarceration for FNIM people living in urban settings.

Mental health and cultural continuity among an urban Indigenous population in Toronto, Canada

OBJECTIVES

Mental health and psychiatric disorders significantly affect individuals on personal and social levels. Indigenous populations in Canada have disproportionately high rates of mental health diagnoses. Our Health Counts (OHC) Toronto assessed mental health, racism, family disruption, and cultural continuity among urban Indigenous people. The objectives of this study were to understand (1) the demographics and characteristics of Indigenous adults with a diagnosed psychological/mental health disorder and (2) potential associations of psychological/mental health diagnoses with experiences of colonization and cultural continuity among Indigenous adults in Toronto.

METHODS

Using community-based participatory research methods, Indigenous adults in Toronto were recruited by respondent-driven sampling (RDS) to complete a comprehensive health assessment survey. RDS-II weights were applied to calculate population-based estimates, and adjusted odds ratios with 95% confidence intervals were produced using logistic regression, controlling for age and gender.

RESULTS

Among Indigenous adults, nearly half (45%) reported receiving a mental health diagnosis. Participants reported lifetime anxiety disorders (53%), major depression (51%), and high rates of suicide ideation (78%). Of Indigenous adults with a diagnosed mental health disorder, 72.7% reported participating in ceremony. Attending residential schools (OR: 7.82) and experiencing discrimination (OR: 2.69) were associated with having a mental health disorder.

CONCLUSION

OHC Toronto responded to the gaps in health assessment data for urban Indigenous people. Despite historic and ongoing trauma, Indigenous people have maintained cultural practices and a strong sense of identity. Efforts aimed at supporting Indigenous well-being must respond to the roots of trauma, racism, and existing Indigenous community knowledge and strengths.

Relationships to land as a determinant of wellness for Indigenous women, two-spirit, trans, and gender diverse people of reproductive age in Toronto, Canada

OBJECTIVE

Disparities in Indigenous reproductive health reflect Canada's historic and ongoing colonial relationship with Indigenous peoples, which includes persistent inequities in health and social services. Reproductive justice scholars and activists advocate for intersectional approaches to enhancing Indigenous health equity that recognize land as a central determinant of wellness. The purpose of this study is to examine the association between relationships to land and wellness in a study of urban Indigenous women, two-spirit, trans, and gender diverse people of reproductive age in Canada's largest city, Toronto.

METHODS

Data were obtained from the cross-sectional Our Health Counts (OHC) Toronto study, which employed respondent-driven sampling methods (n = 323) and a community-directed comprehensive health assessment survey. In an exploratory analysis, we took an Indigenous reproductive justice theoretical approach to multivariable logistic regression.

RESULTS

After adjusting for covariates, there was a statistically significant positive association between relationships to the land and wellness that was estimated with good precision (OR 3.7, 95% CI 2.5-5.3).

CONCLUSION

Our findings indicate that among urban Indigenous women, two-spirit, trans, and gender diverse people of reproductive age there is a positive association between feeling strong in their relationships to land and feeling balanced in the four domains of health (physical, spiritual, mental, and emotional). The community-based, community-directed design of OHC Toronto was congruent with a reproductive justice approach to research. Reproductive justice theories are adaptable to quantitative research on Indigenous reproductive health and can yield novel insights for supporting Indigenous wellness.

Modelling prevalent cardiovascular disease in an urban Indigenous population

OBJECTIVE

Studies have highlighted the inequities between the Indigenous and non-Indigenous populations with respect to the burden of cardiovascular disease and prevalence of predisposing risks resulting from historical and ongoing impacts of colonization. The objective of this study was to investigate factors associated with cardiovascular disease (CVD) within and specific to the Indigenous peoples living in Toronto, Ontario, and to evaluate the reliability and validity of the resulting model in a similar population.

METHODS

The Our Health Counts Toronto study measured the baseline health of Indigenous community members living in Toronto, Canada, using respondent-driven sampling. An iterative approach, valuing information from the literature, clinical insight and Indigenous lived experiences, as well as statistical measures was used to evaluate candidate predictors of CVD (self-reported experience of discrimination, ethnic identity, health conditions, income, education, age, gender and body size) prior to multivariable modelling. The resulting model was then validated using a distinct, geographically similar sample of Indigenous people living in Hamilton, Ontario, Canada.

RESULTS

The multivariable model of risk factors associated with prevalent CVD included age, diabetes, hypertension, body mass index and exposure to discrimination. The combined presence of diabetes and hypertension was associated with a greater risk of CVD relative to those with either condition and was the strongest predictor of CVD. Those who reported previous experiences of discrimination were also more likely to have CVD. Further study is needed to determine the effect of body size on risk of CVD in the urban Indigenous population. The final model had good discriminative ability and adequate calibration when applied to the Hamilton sample.

CONCLUSION

Our modelling identified hypertension, diabetes and exposure to discrimination as factors associated with cardiovascular disease. Discrimination is a modifiable exposure that must be addressed to improve cardiovascular health among Indigenous populations.

Uncovering SARS-COV-2 vaccine uptake and COVID-19 impacts among First Nations, Inuit and Métis Peoples living in Toronto and London, Ontario

Background:

First Nations, Inuit and Métis Peoples across geographies are at higher risk of SARS-CoV-2 infection and COVID-19 because of high rates of chronic disease, inadequate housing and barriers to accessing health services. Most Indigenous Peoples in Canada live in cities, where SARS-CoV-2 infection is concentrated. To address gaps in SARS-CoV-2 information for these urban populations, we partnered with Indigenous agencies and sought to generate rates of SARS-CoV-2 testing and vaccination, and incidence of infection for First Nations, Inuit and Métis living in 2 Ontario cities.

Methods:

We drew on existing cohorts of First Nations, Inuit and Métis adults in Toronto (n = 723) and London (n = 364), Ontario, who were recruited using respondent-driven sampling. We linked to ICES SARS-CoV-2 databases and prospectively monitored rates of SARS-CoV-2 testing, diagnosis and vaccination for First Nations, Inuit and Métis, and comparator city and Ontario populations.

Results:

We found that SARS-CoV-2 testing rates among First Nations, Inuit and Métis were higher in Toronto (54.7%, 95% confidence interval [CI] 48.1% to 61.3%) and similar in London (44.5%, 95% CI 36.0% to 53.1%) compared with local and provincial rates. We determined that cumulative incidence of SARS-CoV-2 infection was not significantly different among First Nations, Inuit and Métis in Toronto (7364/100 000, 95% CI 2882 to 11 847) or London (7707/100 000, 95% CI 2215 to 13 200) compared with city rates. We found that rates of vaccination among First Nations, Inuit and Métis in Toronto (58.2%, 95% CI 51.4% to 64.9%) and London (61.5%, 95% CI 52.9% to 70.0%) were lower than the rates for the 2 cities and Ontario.

Interpretation:

Although Ontario government policies prioritized Indigenous populations for SARS-CoV-2 vaccination, vaccine uptake was lower than in the general population for First Nations, Inuit and Métis Peoples in Toronto and London. Ongoing access to culturally safe testing and vaccinations is urgently required to avoid disproportionate hospital admisson and mortality related to COVID-19 in these communities.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

Long-distance travel for birthing among Indigenous and non-Indigenous pregnant people in Canada

BACKGROUND:

For Indigenous Peoples in Canada, birthing on or near traditional territories in the presence of family and community is of foundational cultural and social importance. We aimed to evaluate the association between Indigenous identity and distance travelled for birth in Canada.

METHODS:

We obtained data from the Maternity Experiences Survey, a national population-based sample of new Canadian people aged 15 years or older who gave birth (defined as mothers) and were interviewed in 2006–2007. We compared Indigenous with non-Indigenous Canadian-born mothers and adjusted for geographic and sociodemographic factors and medical complications of pregnancy using multivariable logistic regression. We categorized the primary outcome, distance travelled for birth, as 0 to 49, 50 to 199 or 200 km or more.

RESULTS:

We included 3100 mothers living in rural or small urban areas, weighted to represent 31 100 (1800 Indigenous and 29 300 non-Indigenous Canadian-born mothers). We found that travelling 200 km or more for birth was more common among Indigenous compared with non-Indigenous mothers (9.8% v. 2.0%, odds ratio [OR] 5.45, 95% confidence interval [CI] 3.52–8.48). In adjusted analyses, the association between Indigenous identity and travelling more than 200 km for birth was even stronger (adjusted OR 16.44, 95% CI 8.07–33.50) in rural regions; however, this was not observed in small urban regions (adjusted OR 1.04, 95% CI 0.37–2.91).

INTERPRETATION:

Indigenous people in Canada experience striking inequities in access to birth close to home compared with non-Indigenous people, primarily in rural areas and independently of medical complications of pregnancy. This suggests inequities are rooted in the geographic distribution of and proximal access to birthing facilities and providers for Indigenous people.

A call for action that cannot go to voicemail: Research activism to urgently improve Indigenous perinatal health and wellbeing

In this call to action, a coalition of Indigenous and non-Indigenous researchers from Australia, Aotearoa New Zealand, United States and Canada argue for the urgent need for adequately funded Indigenous-led solutions to perinatal health inequities for Indigenous families in well-resourced settler-colonial countries. Authors describe examples of successful community-driven programs making a difference and call on all peoples to support and resource Indigenous-led perinatal health services by providing practical actions for individuals and different groups.

Conceptualising cultural safety at an Indigenous-focused midwifery practice in Toronto, Canada: qualitative interviews with Indigenous and non-Indigenous clients

OBJECTIVE

Cultural safety is an Indigenous concept that can improve how healthcare services are delivered to both Indigenous and non-Indigenous peoples in Canada. This study explored how Indigenous and non-Indigenous clients at an urban, Indigenous-focused midwifery practice in Toronto, Canada (Seventh Generation Midwives Toronto, SGMT) conceptualised and experienced culturally safe care.

DESIGN AND SETTING

Interviews were conducted with former clients of SGMT as a part of a larger evaluation of the practice. Participants were purposefully recruited. Interviews were transcribed and analysed thematically using an iterative, consensus-based approach and a critical, naturalistic, and decolonising lens.

PARTICIPANTS

Saturation was reached after 20 interviews (n=9 Indigenous participants, n=11 non-Indigenous participants).

RESULTS

Three domains of cultural safety emerged. Each domain included several themes: Relationships and Communication (respect and support for choices; personalised and continuous relationships with midwives; and being different from past experiences); Sharing Knowledge and Practice (feeling informed about the basics of pregnancy, birth, and the postpartum period; and having access to Indigenous knowledge and protocols), and Culturally Safe Spaces (feeling at home in practice; and having relationships interconnected with the physical space). While some ideas were shared across groups, the distinctions between the Indigenous and non-Indigenous participants were prominent.

CONCLUSION

The Indigenous participants conceptualised cultural safety in ways that highlight the survival and resurgence of Indigenous values, understandings, and approaches in cities like Toronto, and affirm the need for Indigenous midwives. The non-Indigenous participants conceptualised cultural safety with both congruence, illuminating Black-Indigenous community solidarities in cultural safety, and divergence, demonstrating the potential of Indigenous spaces and Indigenous-focused midwifery care to also benefit midwifery clients of white European descent. We hope that the positive impacts documented here motivate evaluators and healthcare providers to work towards a future where 'cultural safety' becomes a standard of care.

Unmet health needs and discrimination by healthcare providers among an Indigenous population in Toronto, Canada

Objectives

Inequalities between Indigenous and non-Indigenous peoples in Canada persist. Despite the growth of Indigenous populations in urban settings, information on their health is scarce. The objective of this study is to assess the association between experience of discrimination by healthcare providers and having unmet health needs within the Indigenous population of Toronto.

Methods

The Our Health Counts Toronto (OHCT) database was generated using respondent-driven sampling (RDS) to recruit 917 self-identified Indigenous adults within Toronto for a comprehensive health assessment survey. This cross-sectional study draws on information from 836 OHCT participants with responses to all study variables. Odds ratios and 95% confidence intervals were estimated to examine the relationship between lifetime experience of discrimination by a healthcare provider and having an unmet health need in the 12 months prior to the study. Stratified analysis was conducted to understand how information on access to primary care and socio-demographic factors influenced this relationship.

Results

The RDS-adjusted prevalence of discrimination by a healthcare provider was 28.5% (95% CI 20.4–36.5) and of unmet health needs was 27.3% (95% CI 19.1–35.5). Discrimination by a healthcare provider was positively associated with unmet health needs (OR 3.1, 95% CI 1.3–7.3).

Conclusion

This analysis provides new evidence linking discrimination in healthcare settings to disparities in healthcare access among urban Indigenous people, reinforcing existing recommendations regarding Indigenous cultural safety training for healthcare providers. Our study further demonstrates Our Health Counts methodologies, which employ robust community partnerships and RDS to address gaps in health information for urban Indigenous populations.

Postpartum depression prevalence and risk factors among Indigenous, non-Indigenous and immigrant women in Canada

OBJECTIVES

The social position of different minority groups in contemporary societies suggests different risk factors for postpartum depression (PPD). In this study, we used two cut-offs of the Edinburgh Postpartum Depression Scale (EPDS) to examine prevalence and risk factors for PPD among mothers participating in the Canadian Maternity Experiences Survey (MES), and to compare Indigenous, Canadian-born non-Indigenous and immigrant mothers.

METHODS

We used cross-sectional nationwide data from the 2006 MES (unweighted N = 6237, weighted N = 74,231) and conducted multivariate logistic regression models for EPDS ≥ 10 and EPDS ≥ 13 to explore risk factors for the total sample of mothers and in each study group.

RESULTS

Prevalence (%, 95 % CI) of EPDS ≥ 10 and EPDS ≥ 13 was significantly higher among immigrant (12.2 %, 10.2-14.2 and 24.1 %, 21.5-26.7) and Indigenous (11.1 %, 7.5-14.7 and 21.2 %, 16.5-25.9) compared to Canadian-born non-Indigenous mothers (5.6 %, 4.9-6.3 and 12.9 %, 11.9-13.9). Multivariate analysis of the total sample showed similar risk factors for EPDS ≥ 10 and EPDS ≥ 13 (ethnicity, low education, ≥ low income cut-off, taking antidepressants, experiencing abuse, low social support). Stratification by study group revealed differing risk factors in each group for EPDS ≥ 10 and EPDS ≥ 13. Indigenous mothers had the most distinct risk factors, followed by immigrant mothers. Non-indigenous Canadian-born mothers had risk factors most similar to the total sample.

CONCLUSION

Differing prevalence and risk factors for PPD within and across study groups suggest that instead of a universal approach, tailored programs and services to prevent PPD in Indigenous, immigrant and non-Indigenous Canadian-born groups could better protect the mental health of Canadian mothers.

Our Health Counts Toronto: using respondent-driven sampling to unmask census undercounts of an urban indigenous population in Toronto, Canada

OBJECTIVES

To provide evidence of the magnitude of census undercounts of 'hard-to-reach' subpopulations and to improve estimation of the size of the urban indigenous population in Toronto, Canada, using respondent-driven sampling (RDS).

DESIGN

Respondent-driven sampling.

SETTING

The study took place in the urban indigenous community in Toronto, Canada. Three locations within the city were used to recruit study participants.

PARTICIPANTS

908 adult participants (15+) who self-identified as indigenous (First Nation, Inuit or Métis) and lived in the city of Toronto. Study participants were generally young with over 60% of indigenous adults under the age of 45 years. Household income was low with approximately two-thirds of the sample living in households which earned less than $C20 000 last year.

PRIMARY AND SECONDARY OUTCOME MEASURES

We collected baseline data on demographic characteristics, including indigenous identity, age, gender, income, household type and household size. Our primary outcome asked: 'Did you complete the 2011 Census Canada questionnaire?'

RESULTS

Using RDS and our large-scale survey of the urban indigenous population in Toronto, Canada, we have shown that the most recent Canadian census underestimated the size of the indigenous population in Toronto by a factor of 2 to 4. Specifically, under conservative assumptions, there are approximately 55 000 (95% CI 45 000 to 73 000) indigenous people living in Toronto, at least double the current estimate of 19 270.

CONCLUSIONS

Our indigenous enumeration methods, including RDS and census completion information will have broad impacts across governmental and health policy, potentially improving healthcare access for this community. These novel applications of RDS may be relevant for the enumeration of other 'hard-to-reach' populations, such as illegal immigrants or homeless individuals in Canada and beyond.

Efficacy, safety, tolerability and pharmacokinetics of a novel human immune globulin subcutaneous, 20%: a Phase 2/3 study in Europe in patients with primary immunodeficiencies

A highly concentrated (20%) immunoglobulin (Ig)G preparation for subcutaneous administration (IGSC 20%), would offer a new option for antibody replacement therapy in patients with primary immunodeficiency diseases (PIDD). The efficacy, safety, tolerability and pharmacokinetics of IGSC 20% were evaluated in a prospective trial in Europe in 49 patients with PIDD aged 2–67 years. Over a median of 358 days, patients received 2349 IGSC 20% infusions at monthly doses equivalent to those administered for previous intravenous or subcutaneous IgG treatment. The rate of validated acute bacterial infections (VASBIs) was significantly lower than 1 per year (0·022/patient‐year, P < 0·0001); the rate of all infections was 4·38/patient‐year. Median trough IgG concentrations were ≥ 8 g/l. There was no serious adverse event (AE) deemed related to IGSC 20% treatment; related non‐serious AEs occurred at a rate of 0·101 event/infusion. The incidence of local related AEs was 0·069 event/infusion (0·036 event/infusion, when excluding a 13‐year‐old patient who reported 79 of 162 total related local AEs). The incidence of related systemic AEs was 0·032 event/infusion. Most related AEs were mild, none were severe. For 64·6% of patients and in 94·8% of IGSC 20% infusions, no local related AE occurred. The median infusion duration was 0·95 (range = 0·3‐4·1) h using mainly one to two administration sites [median = 2 sites (range = 1–5)]. Almost all infusions (99·8%) were administered without interruption/stopping or rate reduction. These results demonstrate that IGSC 20% provides an effective and well‐tolerated therapy for patients previously on intravenous or subcutaneous treatment, without the need for dose adjustment.

Gastric electrical stimulation for the treatment of diabetic gastroparesis

Diabetic gastroparesis is a component of autonomic neuropathy, and is the most common manifestation of gastrointestinal neuropathy. Diabetes is responsible for about one quarter of gastroparesis. The upper gastrointestinal symptoms are often non-specific and dominated by nausea, vomiting, early satiety, fullness, bloating. We also have to look for diabetic gastroparesis in case of metabolic instability, such as postprandial hypoglycaemia. The pathophysiology of diabetic gastroparesis is complex, partly due to a vagus nerve damage, but also to changes in secretion of hormones such as motilin and ghrelin. A decrease in the stem cell factor (SCF), growth factor for cells of Cajal (gastric pacemaker), was found in subjects with diabetic gastroparesis. These abnormalities lead to an excessive relaxation in the corpus, a hypomotility of antrum, a desynchronization antrum-duodenum-pylorus, and finally an abnormal duodenal motility. The treatment of diabetic gastroparesis is based on diabetes control, and split meals by reducing the fiber content and fat from the diet. The antiemetic and prokinetic agents should be tested primarily in people with nausea and vomiting. Finally, after failure of conventional measures, the use of gastric neuromodulation is an effective alternative, with well-defined indications. Introduced in the 1970s, this technology works by applying electrical stimulation continues at the gastric antrum, particularly in patients whose gastric symptoms are refractory to other therapies. Its efficacy has been recently reported in different causes of gastroparesis, especially in diabetes. Gastric emptying based on gastric scintigraphy, gastrointestinal symptoms, biological markers of glycaemic control and quality of life are partly improved, but not normalized. Finally, a heavy nutritional care is sometimes necessary in the most severe forms. The enteral route should be preferred (nasojejunal and jejunostomy if possible efficiency). However, in case of failure especially in patients with small bowel neuropathy, the long-term parenteral nutrition is sometimes required.

Collapse of the N=28 shell closure in (42)Si

The energies of the excited states in very neutron-rich (42)Si and (41,43)P have been measured using in-beam gamma-ray spectroscopy from the fragmentation of secondary beams of (42,44)S at 39A MeV. The low 2(+) energy of (42)Si, 770(19) keV, together with the level schemes of (41,43)P, provides evidence for the disappearance of the Z=14 and N=28 spherical shell closures, which is ascribed mainly to the action of proton-neutron tensor forces. New shell model calculations indicate that (42)Si is best described as a well-deformed oblate rotor.

Enhanced core polarization in (70)Ni and (74)Zn

The reduced transition probabilities B(E2;0(+) --> 2(+)(1)) of the neutron-rich (74)Zn and (70)Ni nuclei have been measured by Coulomb excitation in a (208)Pb target at intermediate energy. These nuclei have been produced at Grand Accélérateur National d'Ions Lourds via interactions of a 60A MeV (76)Ge beam with a Be target. The B(E2) value for (70)Ni(42) is unexpectedly large, which indicates that neutrons added above N=40 strongly polarize the Z=28 proton core. In the Zn isotopic chain, the steep rise of B(E2) values beyond N=40 continues up to (74)Zn(44). The enhanced proton core polarization in (70)Ni is attributed to the monopole interaction between the neutron in the g(9/2) and protons in the f(7/2) and f(5/2) spin-orbit partner orbitals. This interaction could result in a weakening of magicity in (78)Ni(50).

Excitation energies of superdeformed States in 196Pb: towards a systematic study of the second well in Pb isotopes

The excitation energy of the lowest-energy superdeformed band in 196Pb is established using the techniques of time-correlated gamma-ray spectroscopy. Together with previous measurements on 192Pb and 194Pb, this result allows superdeformed excitation energies, binding energies, and two-proton and two-neutron separation energies to be studied systematically, providing stringent tests for current nuclear models. The results are examined for evidence of a "superdeformed shell gap."

The last common ancestor of Sarcolaenaceae and Asian dipterocarp trees was ectomycorrhizal before the India-Madagascar separation, about 88 million years ago

Phylogenetic studies comparing the Dipterocarpaceae and the Sarcolaenaceae, a tree family endemic to Madagascar, have shown that the Sarcolaenaceae share a common ancestor with Asian dipterocarps. This suggests that Asian dipterocarps drifted away from Madagascar with the India-Seychelles landmass and then dispersed through Asia. Although all dipterocarps examined so far have been found to be ectomycorrhizal, the ectomycorrhizal status of Sarcolaenaceae had not been investigated. Here we establish the ectomycorrhizal status of Sarcolaenaceae using histological and molecular methods. This indicates that the common ancestor of the Sarcolaenaceae and Asian dipterocarps was ectomycorrhizal, at least before the separation of the Madagascar-India landmass, 88 million years ago.

(68)(28)Ni(40): Magicity versus superfluidity

The neutron-rich (66,68)Ni have been produced at GANIL via interactions of a 65.9A MeV 70Zn beam with a 58Ni target. Their reduced transition probability B(E2;0(+)(1)-->2+) has been measured for the first time by Coulomb excitation in a (208)Pb target at intermediate energy. The B(E2) value for (68)Ni(40) is unexpectedly small. An analysis in terms of large scale shell model calculations stresses the importance of proton core excitations to reproduce the B(E2) values and indicates the erosion of the N = 40 harmonic-oscillator subshell by neutron-pair scattering.

Centrifugation and addition of glycerol at 22 degres C instead of 4 degrees C improve post-thaw motility and fertility of stallion spermatozoa

The aims of this study were to evaluate the effects of cooling rate to 4 degrees C and temperature at the time of centrifugation/glycerol-addition (freezing extender: INRA82 + 2% egg yolk + 2.5% glycerol) on postcentrifugation recovery rate, post-thaw motility and per-cycle fertility. When centrifugation/glycerol-addition was performed at 4 degrees C (14 ejaculates), a moderate cooling rate (37 degrees C to 4 degrees C in I h) resulted in higher post-thaw motility (45%) than when using a slow cooling rate (37 degrees C to 4 degrees C in 4 h) (39%; P<0.05). When centrifugation/glycerol-addition was performed at 22 degrees C (37 degrees C to 22 degrees C in 10 min) (10 ejaculates), post-thaw motility was lower when spermatozoa were frozen directly from 22 degrees C (23%) than when spermatozoa were cooled to 4 degrees C (22 degrees C to 4 degrees C in 1 h) before freezing (47%; P<0.0001). When centrifugation/glycerol-addition was performed at 22 degrees C (before cooling at a moderate rate), as opposed to 4 degrees C (after cooling at a moderate rate), a significant improvement of 1) recovery of spermatozoa after centrifugation (P<0,0001), 2) post-thaw motility of spermatozoa at thawing (40% vs 36% (n < or = 291 ejaculates/group), P<0.0001) and 3) per-cycle fertility (56% vs 42% (n > or = 190 cycles/group), P<0.01) was observed. In conclusion, centrifugation/glycerol-addition at 22 degrees C followed by cooling to 4 degrees C at a moderate rate results in an improvement of post-thaw motility, spermatozoa recovery rate and per cycle fertility.

Response of naïve and memory CD8+ T cells to antigen stimulation in vivo

We studied the influence of memory T cell properties on the efficiency of secondary immune responses by comparing the in vivo immune response of the same numbers of T cell receptor (TCR) transgenic (Tg) naïve and memory T cells. Compared to naïve Tg cells, memory cells divided after a shorter lag time; had an increased division rate; a lower loss rate; and showed more rapid and efficient differentiation to effector functions. We found that initial naïve T cell priming resulted in cells expressing mutually exclusive effector functions, whereas memory T cells were multifunctional after reactivation, with each individual cell expressing two to three different effector functions simultaneously. These special properties of memory T cells ensure the immediate control of reinfection.

A CpG-rich RNA and an RNA helicase tightly associated with the DNA demethylation complex are present mainly in dividing chick embryo cells

In the developing chicken embryo, active DNA demethylation requires both RNA and proteins (Nucleic Acids Res. 25, 2375-2380, 1997; ibid. 25, 4545-4550, 1997, FEBS Lett. 449, 251-254, 1999a). In vitro assays indicate that in the 5- and 12-day-old embryos the highest specific activity of 5-methylcytosine DNA glycosylase is found in the brain, the eyes and the skin. In situ hybridization with antisense CpG-rich RNA tightly associated to the DNA demethylation complex shows a restricted expression pattern only in proliferating tissues such as the neuroepithelia of the brain in 5-day-old embryos. The RNA is absent in differentiated tissues like the skeletal and heart muscle, liver and the crystallin-producing cells in the lens. The CpG-rich RNA is transcribed in a developmental stage-specific rather than in a cell-specific manner. In contrast transcripts of DNA methyltransferase are found in dividing and quiescent cells. In situ hybridization with a probe of a RNA helicase which is also associated with the DNA demethylation complex shows a very similar localization in mitotically active tissues as the CpG-rich RNA. The content of 5-methylcytosine in individual cells was determined with a specific monoclonal antibody and cytometric analysis on tissue sections. The results indicate that proliferating cells have on the average 15% more methylated cytosines than non-dividing cells. This represents roughly 3x10(6) more methylation sites per haploid genome.

Alterations of DNA methylation patterns in germ cells and Sertoli cells from developing mouse testis

In situ alterations of DNA methylation were studied between 14 d postcoitum and 4 d postpartum in Sertoli cells and germ cells from mouse testis, using anti-5-methylcytosine antibodies. Compared to cultured fibroblasts, Sertoli cells display strongly methylated juxtacentromeric heterochromatin, but hypomethylated chromatids. Germ cells always possess hypomethylated heterochromatin, whereas their euchromatin passes from a demethylated to a strongly methylated status between days 16 and 17 postcoitum. This hypermethylation occurs in the absence of DNA replication, germ cells being blocked in the G(0)-G(1) phase from day 15 postcoitum to birth. The DNA hypermethylation of germ cells is maintained until birth and could be visualized on both chromatids of metaphase chromosomes at the first postpartum cell division. Subsequently, the DNA hypermethylation is lost semiconservatively, being replaced by a methylation pattern recalling the typical fibroblast pattern. These alterations of DNA methylation follow a strict chronology, are chromosome structure and cell-type dependent, and may underlie profound changes of genome function.

Identification and expression of Go1 and Go2 alpha-subunit transcripts in human myometrium in relation to pregnancy

The 39-kDa Goalpha protein, the alpha subunit of a major heterotrimeric G protein of brain and neuroendocrine cells, was found to be present in human myometrium. Using three different antisera, we showed its strong expression in myometrium from pregnant patients as compared to nonpregnant ones. This is in agreement with the high expression level of its two isoforms (alphao1 and alphao2), previously described in late pregnancy. To better ascertain the nature of these immunoreactive isoforms, we investigated transcripts of the Goalpha gene in myometrium from pregnant and nonpregnant patients by reverse transcription-polymerase chain reaction (RT-PCR). In this tissue, the amplified cDNA product of a region common to both Go1alpha and Go2alpha mRNA variants was recognized as the Goalpha nucleotide sequence. Transcripts of Go1alpha and Go2alpha were identified by sequencing. A partial cDNA Go2alpha sequence was described, which differed from the Goalpha gene by two nucleotides in exon 8B. Levels of Go1alpha and Go2alpha transcripts analyzed by semi-quantitative RT-PCR were significantly higher in myometrium from pregnant than from nonpregnant patients. It is suggested that Goalpha gene expression in this tissue may contribute to modifications seen in the signaling pathways observed at the end of pregnancy.

Embryo-maternal interactions at the implantation site: a delicate equilibrium

Blastocyst implantation and successful establishment of pregnancy require delicate interactions between the embryo and the maternal environment. During preimplantation, maternal/embryo communication is mediated by the trophectoderm. In the late luteal phase, physiological changes occur in the endometrium to allow blastocyst implantation. The "window of implantation" represents the period of maximum uterine receptivity for implantation. In response to signals from the embryo, pregnancy-specific proteins are released in maternal serum and a series of morphological, biochemical and immunological changes occur in the uterine environment. These systemic and local modifications can be considered to constitute "the maternal recognition of pregnancy". The human hemochorial placenta arises primarily through proliferation, migration and invasion of the endometrium and its vasculature by the embryonic trophoblast. The complex invasive processes accompanying implantation of the embryo are controlled at the embryo-maternal interface by factors from decidualized endometrium and the trophoblast itself. An inflammatory reaction and a proper maternal immune response allow survival and development of the feto-placental unit. In this review, we focus on interactions between trophoblast and uterine tissues and on cellular mechanisms and molecular signals involved in the closely regulated process of implantation.

Heparin-like structures on respiratory syncytial virus are involved in its infectivity in vitro

Addition of heparin to the virus culture inhibited syncytial plaque formation due to respiratory syncytial virus (RSV). Moreover, pretreatment of the virus with heparinase or an inhibitor of heparin, protamine, greatly reduced virus infectivity. Two anti-heparan sulfate antibodies stained RSV-infected cells, but not noninfected cells, by immunofluorescence. One of the antibodies was capable of neutralizing RSV infection in vitro. These results prove that heparin-like structures identified on RSV play a major role in early stages of infection. The RSV G protein is the attachment protein. Both anti-heparan sulfate antibodies specifically bound to this protein. Enzymatic digestion of polysaccharides in the G protein reduced the binding, which indicates that heparin-like structures are on the G protein. Such oligosaccharides may therefore participate in the attachment of the virus.

Immune response to baculovirus expressed protein fragment amino acids 190-289 of respiratory syncytial virus (RSV) fusion protein

At least two neutralizing epitopes have been identified in the amino acid (aa) sequence 190-289 of the RSV fusion protein. The authors expressed this region in insect cells (bF190-289) and compared the immune response to bF190-289 with that induced by baculovirus expressed full-length fusion protein (bF). As with bF, mice primed with bF190-289 produced exclusively antibodies of IgG1 isotype, generated neutralizing antibodies, reduced significantly the virus titer (about a half log10 reduction) after RSV challenge and induced a Helper T (Th) 2 cell response in mediastinal lymph node cells (MLNC) restimulated in vitro. Thus, the aa sequence 190-289 represents a major immunogenic region of the RSV fusion protein.

Modifications of CD8+ T cell function during in vivo memory or tolerance induction

Naive monoclonal T cells specific for the male antigen can be stimulated in vivo to eliminate male cells and become memory cells or to permit survival of male cells and become tolerant. Memory cells responded to TCR ligation by cyclic oscillations of calcium levels and immediate secretion of very high levels of IL-2 and interferon-gamma. Tolerant cells did not proliferate in response to ionomycin and phorbol myristate acetate, failing to mobilize calcium to produce IL-2 or express IL-2R, but survived for long time periods in vivo and secreted IL-10. These results emphasize that tolerance is not an absence of all functional activity and may be associated with modifications of behavior conferring important regulatory functions on tolerant T cells.

Effects of trace element and/or vitamin supplementation on vitamin and mineral status, free radical metabolism and immunological markers in elderly long term-hospitalized subjects. Geriatric Network MIN. VIT. AOX

A randomized double-blind trial was performed in order to assess the efficacity of differing combinations of antioxidant nutrients on biochemical parameters of vitamin and trace element status, immunological parameters and free radical metabolism in elderly long term hospitalized subjects. A total of 756 institutionalized elderly subjects were recruited in 26 nursing homes in different areas of France. Four groups were constituted, receiving daily, for 1 year, either vitamins (beta-carotene, 6 mg; vitamin C, 120 mg; and vitamin E, 15 mg), trace elements (zinc, 20 mg and selenium, 100 micrograms), trace elements associated with vitamins, or a placebo. Biochemical indicators of trace elements and vitamin status and free radical parameters were measured before and after 6 months and 1 year of supplementation. Some immunological markers were investigated initially and after 6 months of supplementation on a subsample of 134 subjects. Mean plasma levels of alpha-tocopherol, gamma-tocopherol, vitamin C, alpha-carotene, beta-carotene and copper increased significantly after 6 months of supplementation in groups receiving vitamins alone or associated with trace elements. Serum selenium concentrations were significantly increased at 6 months of supplementation, and serum zinc only after one year in the trace element groups. Serum lycopene levels were significantly decreased by trace element supplementation. A significant increase in Se-glutathione peroxidase (GPx) levels was observed in groups receiving trace elements alone or associated with vitamins. No effect was noted on superoxide dismutase (SOD) activity or TBARs production. No effect of supplementation was found for in vitro lymphocyte proliferative responses or most lymphocyte subsets, except for a significantly lower percentage of CD2 subsets observed in groups receiving mineral supplementation either alone or associated with vitamins. A significant difference in CD19 subsets was found in groups receiving trace elements. Mean IL-1 production was significantly higher after 6 months of supplementation in the vitamin groups.

Prophylactic administration of a complementarity-determining region derived from a neutralizing monoclonal antibody is effective against respiratory syncytial virus infection in BALB/c mice

Immunotherapy with antibodies against respiratory syncytial virus (RSV) is a treatment option given the absence of any vaccine or other available satisfactory treatment. We selected one of our monoclonal antibodies, RS-348, that is highly neutralizing. We showed that a single peptide (PEP3H) derived from complementarity-determining region 3 (CDR3) of its heavy chain was capable of neutralizing the virus in vitro. When intranasally administered 24 h before challenge, this peptide protected BALB/c mice against RSV lung infection. These results indicate that a single CDR can be effective against RSV infection.

Malignant melanoma and granulomatosis

Sarcoidosis or granulomatous reactions have rarely been reported in association with malignant melanoma (MM). We describe seven patients who presented with both granulomatous disease and MM, and discuss the physiopathological and prognostic significance of this association. In three patients, the granulomatosis was diagnosed as true sarcoidosis and in one patient, as tumour-associated granuloma. In three cases, designated here as atypical tumour-associated granulomatoses, the presence of clear-cut pulmonary granulomatous nodules was typical neither for sarcoidosis nor for tumour-associated granuloma and was highly suggestive of melanoma metastases. Mediastinal lymphadenopathy was present in every patient. In all seven patients, the question of mediastinal or pulmonary involvement or relapse of the MM was raised, but could be confirmed in only one patient. MM can be associated with granulomatous disease. Knowledge of this association has implications in the management of patients with MM.

Value of a ligase chain reaction assay for detection of ganciclovir resistance-related mutation 594 in UL97 gene of human cytomegalovirus

Human cytomegalovirus (HCMV) isolates resistant to ganciclovir were found in patients undergoing therapy. Therefore, we have developed a new specific and sensitive method--a ligase chain reaction (LCR) assay--for detection of frequently encountered 594 mutated codon in ganciclovir (GCV) resistant virus. Previous studies characterized an alanine to valine change on codon 594 in resistant strains. A novel substitution in 594, alanine to glycine, is described which is also capable of conferring ganciclovir resistance. LCR products were analyzed on polyacrylamide gel- and the mutant was detected using a non radioactive method. The LCR product detection was then adapted to a microtitre plate format with a colorimetric detection. This method allowed the distinction of mutated GCV-resistant strains from sensitive strains with a high sensitivity, and the detection of a low percentage of mutated DNA in virus load. This assay could be useful in following the evolution of mutated DNA compared to viral infection.

Endothelin-1 and ETA receptor expression in vascular smooth muscle cells from human placenta: a new ETA receptor messenger ribonucleic acid is generated by alternative splicing of exon 3

Endothelin-1 (ET-1) is a potent vasoactive peptide in stem villi vessels, which are considered to be the major sites of placental vascular resistance. To investigate the influence of pregnancy-specific hormonal environment on ET and ET receptor (ET-R) expression, we first developed and characterized a culture of vascular smooth muscle cells from stem villi vessels. Secondly, we investigated whether the muscular layer of stem villi vessels could be a site of the ET expression described in the placenta, and we examined this expression in placental vascular smooth muscle cells (PVSMCs). Prepro-ET-1 and prepro-ET-3 messenger ribonucleic acid (mRNA) were identified in stem villi vessels, whereas only prepro-ET-1 mRNA was observed in PVSMCs. Third, with the goal of using PVSMCs as ET target cells, we characterized the ET-R expressed by these cells in comparison with the muscular layer of stem villi vessels. Whereas both ETA-R and ETB-R are present in stem villi vessels, we found that PVSMCs express exclusively ETA-R. In addition to the previously reported ETA-R spliced transcripts, we described a new ETA-R transcript, ETA-R delta 3, generated by exclusion of exon 3 in stem villi vessels and PVSMCs. Alternative splicing mechanisms of ETA-R mRNA could constitute a control of the abundance of active ETA-R in terms of contractility. PVSMCs will be a useful model to study the environmental stimuli involved in the regulation of ET and ET-R expression in the muscular layer of feto-placental vasculature.

AIDS-related primary brain lymphomas: histopathologic and immunohistochemical study of 51 cases. The French Study Group for HIV-Associated Tumors

Fifty-one cases of acquired immunodeficiency syndrome (AIDS)-related primary brain lymphomas (AR-PBL) were investigated for clinical characteristics; human immunodeficiency virus (HIV)-associated disorders; histopathologic features; immunophenotype; Epstein-Barr virus (EBV) infection; and, when frozen tissue was available, oncogene rearrangements. AR-PBL occurred late in the course of AIDS and were usually associated with other systemic or cerebral disorders and with a low level of CD4 lymphocytes. All cases were high grade lymphomas according to the Working Formulation or updated Kiel classification, and often displayed a multifocal pattern. Thirty cases were classified as immunoblastic with plasmacytic differentiation, 18 cases were large cell lymphomas with an immunoblastic component or centroblastic polymorphic lymphomas, and 2 were small noncleaved non-Burkitt lymphomas (Working Formulation). This latter category is classified as Burkitt's-like lymphoma in the REAL nomenclature. One case could not be classified because of necrosis. AR-PBL showed a high level expression of activation and adhesion molecules. The presence of EBV was detected in most cases, and, when PCR was used, this was a constant finding. bcl-2 oncoprotein and latent membrane protein-1 (LMP-1) were strongly expressed. None of the tested cases expressed p53, or were rearranged for bcl-2 or c-myc oncogenes. This study confirms the immunophenotypic specificity of AR-PBL, which may reflect the special immune status of the brain.

Cross-reactive and group-specific immune responses to a neutralizing epitope of the human respiratory syncytial virus fusion protein

Immune responses to a synthetic peptide corresponding to amino-acids 205-225 of the fusion protein from group B respiratory syncytial (RS) virus, were studied in mice and rabbits, and compared to a similar peptide from group A RS virus. Peptide 205-225 (B) was recognized by monoclonal antibody RS-348, and was immunogenic in both mice and rabbits, as was peptide 205-225 from the fusion protein of a group A strain. Peptide 205-225 (B) induced a proliferative T-cell response, demonstrating the existence of a T-cell epitope in this region of the fusion protein of group B viruses. Both peptides were able to induce a T-cell cross-reactive proliferation when mice were primed with either the homologous or the heterologous peptide. ELISA were performed using synthetic peptides or whole virus (from group A and B) as antigens. Mice anti-peptide sera recognized both homologous and heterologous peptides. A similar pattern was observed with RS virus strains. In indirect immunofluorescence assays, both anti-peptide rabbit sera recognized human nasal epithelial cells infected with A or B strains of RS virus. In contrast, while anti-peptide 205-225 rabbit serum from group A neutralized group A and B strains of RS virus, anti-peptide 205-225 rabbit serum from group B was unable to neutralize a group A virus, although it neutralized a group B strain. These results are similar to the immune response observed in children following primary RS virus infection.

G protein expression in human fetoplacental vascularization. Functional evidence for Gs alpha and Gi alpha subunits

GTP-binding proteins are key elements in coupling receptors to various effector systems. Using ADP-ribosylation by cholera (CTX) and pertussis (PTX) toxins and an immunodetection technique, we investigated the G protein expression profile in smooth muscle of stem villi vessels obtained from human term placentae. In placental vascular smooth muscle, we report the presence of two CTX-protein substrates of 42 and 45 kDa recognized by Gs alpha antibodies, and three Gi alpha isoforms, substrates of PTX, identified as Gi1 alpha, Gi3 alpha (two proteins of 41 kDa) and Gi2 alpha (a 40-kDa protein). We also characterized another target of PTX, a 40-kDa Go alpha-immunoreactive protein and detected the PTX-insensitive Gq-Gi1 alpha proteins. To assess the functional significance of the G alpha proteins identified in this tissue, we measured the adenylyl cyclase activity in the presence of guanyl nucleotides alone or with increasing concentrations of vasoactive intestinal peptide (VIP), and examined whether VIP-bound sites, in the presence of GTP gamma S, promote the release of G alpha proteins from the membranes of vascular smooth muscle. At low concentrations (0.1 nM to 0.01 microM), guanyl nucleotides stimulated adenylyl cyclase activity in a dose-dependent manner, while at higher concentrations (10 microM to 1 mM) the stimulation rate of cAMP production by guanyl nucleotides decreased. In a dose-dependent manner, VIP in the presence of GTP gamma S increased adenylyl cyclase activity and specifically promoted the release of both Gs alpha isoforms. In contrast, the release of Gi1 and Gi2 alpha isoforms was not significantly increased in the presence of VIP, while GTP gamma S alone stimulated their release. Our data show physical evidence of the activation of Gs proteins by VIP-bound membrane receptors, resulting in dissociation and release of Gs alpha subunits in the soluble fraction. They assess the specific coupling of the two Gi alpha isoforms to VIP receptors in smooth muscle wall of placental stem villi vessels. It would be of interest to investigate whether changes in Gs alpha expression and/or function are associated with the placental angiogenesis process during pregnancy.

Expression of endothelin precursor genes in human trophoblast in culture

We have shown previously the presence of immunoreactive endothelin in cultured trophoblastic cells from human term placenta as well as in the trophoblast-conditioned medium. To confirm whether or not the differentiated syncytiotrophoblast is a site for endothelin synthesis, we investigated, by reverse transcription and polymerase chain reaction, the expression of the three preproendothelin genes in 3-day cultured trophoblast. While no endothelin-2 precursor mRNA was detected, preproendothelin-1 mRNA was found to be expressed by the trophoblast. The endothelin-3 precursor gene was also expressed, but at low level and it was detected only after Southern blotting and oligonucleotide hybridization. The ability of trophoblast in culture to express the endothelin precursor genes supports the idea that, in human term placenta, villous syncytiotrophoblast that lines the intervillous space containing maternal blood acts as an endothelial layer.

Protein tyrosine kinases in activation signal of human basophils through the immunoglobulin E receptor type l

Human basophils activated through high-affinity immunoglobulin E (IgE) receptors (Fc epsilon RI) are involved in the late phase of the allergic reaction. To investigate the possible involvement of protein-tyrosine kinases in this activation we used human acute basophilic leukemia (ABL) cells in culture as well as a pure population of normal basophils in vitro-derived from human bone marrow precursor cells (HBMB). ABL cells were 50-80% basophils at various stages of maturation as assessed by staining, morphology, ultrastructure, and flow cytometry analysis, and only basophils in ABL cells expressed Fc epsilon RI. Aggregation of Fc epsilon RI by IgE and anti-IgE, IgE and antigen, or anti-Fc epsilon RI monoclonal antibodies on ABL cells or on HBMB, led to increased tyrosine phosphorylation of 120-, 100-, 80-, 72-, 50- to 65-, and 38-kDa substrates. Tyrosine phosphorylations in ABL cells were in basophils because 1) they were detected after a 5-s stimulation, 2) they were observed under conditions where mediator release is minimal, i.e., in the absence of extracellular calcium, 3) hapten addition during antigen stimulation resulted in almost total disappearance of tyrosine phosphorylations within 30 s. There was correlation between histamine release and tyrosine phosphorylation in anti-IgE dose-responses and in dose-responses of the tyrosine kinase inhibitor genistein. The tyrosine kinase p72syk was detected in the cells. Stimulation of ABL cells for 1 min resulted in extracellular calcium-independent tyrosine phosphorylation and activation of p72syk. Therefore, tyrosine kinases are involved in the early steps of human Fc epsilon RI signaling in basophils. Tyrosine kinases and their substrates could represent new potential therapeutic targets to prevent the development of the allergic reaction.