Thymic stromal lymphopoietin plays divergent roles in murine models of atopic and nonatopic airway inflammation.

BACKGROUND: Thymic stromal lymphopoietin (TSLP) is a cytokine primarily produced by epithelial cells, which has been shown to be a potent inducer of T-helper 2 (Th2)-type responses. However, TSLP has pleiotropic effects upon immune cells, and although extensively studied in the context of atopic asthma, its relevance as a therapeutic target and its role in the pathogenesis of nonatopic asthma remains unknown. We sought to investigate the role of TSLP in atopic, nonatopic and viral-induced exacerbations of pulmonary inflammation. METHODS: Using stringently defined murine models of atopic, nonatopic and virally exacerbated forms of pulmonary inflammation, we compared inflammatory responses of C57BL/6 wild-type (WT) and TSLP receptor-deficient (TSLPR KO) mice. RESULTS: Thymic stromal lymphopoietin receptor (TSLPR) signaling was crucial for the development of atopic asthma. Specifically, TSLPR signaling to lung recruited CD4+ T cells enhanced eosinophilia, goblet cell hyperplasia, and overall inflammation within the airways. In contrast, the absence of TSLPR signaling was associated with strikingly exaggerated pulmonary neutrophilic inflammation in a nonatopic model of airway inflammation. The inflammation was associated with excessive levels of interleukin (IL)-17A in the lungs, indicating that TSLP negatively regulates IL-17A. In addition, in a model of influenza-induced exacerbation of atopic airway inflammation, the absence of TSLPR signaling also led to exaggerated neutrophilic inflammation. CONCLUSION: Thymic stromal lymphopoietin plays divergent roles in the pathogenesis of atopic and nonatopic asthma phenotypes by either enhancing Th2 responses or curtailing T-helper 17 responses. These findings raise important caveats for the design of therapeutic interventions targeting TSLP in asthma.

TSLP promotes influenza-specific CD8+ T-cell responses by augmenting local inflammatory dendritic cell function.

Thymic stromal lymphopoietin (TSLP) is a mucosal tissue-associated cytokine that has been widely studied in the context of T helper type 2 (Th2)-driven inflammatory disorders. Although TSLP is also produced upon viral infection in vitro, the role of TSLP in antiviral immunity is unknown. In this study we report a novel role for TSLP in promoting viral clearance and virus-specific CD8+ T-cell responses during influenza A infection. Comparing the immune responses of wild-type and TSLP receptor (TSLPR)-deficient mice, we show that TSLP was required for the expansion and activation of virus-specific effector CD8+ T cells in the lung, but not the lymph node. The mechanism involved TSLPR signaling on newly recruited CD11b+ inflammatory dendritic cells (DCs) that acted to enhance interleukin-15 production and expression of the costimulatory molecule CD70. Taken together, these data highlight the pleiotropic activities of TSLP and provide evidence for its beneficial role in antiviral immunity.

Breastfeeding in rural northern India: levels and differentials.

PIP: This paper presents the findings of a study conducted in India, which utilized both the retrospective reporting and the current status reporting of breast-feeding for studying the levels and differentials in the duration of breast-feeding. This study confirms the known differentials of the mean duration of breast-feeding with some explanatory variables and investigates some new differentials. Using data collected from 5 villages in Uttar Pradesh in 1995 and both univariate and multivariate statistical techniques, findings showed an almost universal pattern of breast-feeding in a rural part of northern India. However, compared to past Indian studies, a slightly lower mean duration of breast-feeding was seen. Older mothers with the highest parity were most likely to breast-feed longer compared to others. Education, socioeconomic status, and survival status of the child had significant impacts on the duration of breast-feeding. Overall, this study demonstrates that mothers living in upper strata of the society breast-feed for a shorter duration than their counterparts.^ieng

Postpartum amenorrhoea in rural eastern Uttar Pradesh, India.

This paper calculates the mean duration of the postpartum amenorrhoea (PPA) and examines its demographic, and socioeconomic correlates in rural north India, using data collected through 'retrospective' (last but one child) as well as 'current status' (last child) reporting of the duration of PPA. The mean duration of PPA was higher in the current status than in the retrospective data; the difference being statistically significant. However, for the same mothers who gave PPA information in both the data sets, the difference in mean duration of PPA was not statistically significant. The correlates were identical in both the data sets. The current status data were more complete in terms of the coverage, and perhaps less distorted by reporting errors caused by recall lapse. A positive relationship of the mean duration of PPA was found with longer breast-feeding, higher parity and age of mother at the birth of the child, and the survival status of the child. An inverse relationship was found with higher education of a woman, higher education of her husband and higher socioeconomic status of her household, these variables possibly acting as proxies for women's better nutritional status.

PIP: The differentials of the mean duration of postpartum amenorrhea (PPA) were investigated in a study conducted in five villages in the Varanasi district in Uttar Pradesh State, India, in 1995. Information was collected from 1060 mothers about their last birth and from 767 mothers about the penultimate birth. Following a peak at 1 month's duration, the PPA distribution showed heaping at durations of multiples of 6. The mean duration of PPA was 7.2 months after the birth of the last child and 7.7 months when the duration between the date of the last birth and the survey date was used for the analysis. Survival analysis indicated that the chance of resumption of menses at 3 months postpartum was 44% after the birth of the last child and 49% for the last but one child. The shorter duration of PPA in the latter group may reflect differences between retrospective and current status data quality. Multivariate analysis revealed that the duration of PPA increased with longer durations of breast feeding, higher parity and maternal age, and if the child survived to the next birth or the time of the survey. PPA duration was negatively associated with maternal and paternal education, higher socioeconomic status, and residence in a pukka house--variables that may be proxies for improved maternal nutrition status.

A study of aged population and associated health risks in rural India.

This article examines the prevalence of age-related diseases in different socioeconomic and demographic groups. The study is based on a sample of 267 aged persons (> 60 years) collected through a survey entitled "Aging and Health Conditions in Rural Area-A Sample Survey, 1990" conducted in the rural areas of the Varanasi district of Uttar Pradesh, a northern province of India. Various socio-behavioral factors are found to play a significant role in determining the health conditions of aged people. Also, illiteracy and poverty are found to have their own impact on health during aging. It is also noted that due to adverse familial relationships, many stress-related disorders occur which may result in the poor health of the elderly. Demands for old age pensions were made by most of the elderly people in the sample.

PIP: As part of a broader study of aging and health conditions in rural India, 267 persons over 60 years old from Uttar Pradesh's Varanasi district were interviewed in 1990. Overall, 37% of men and 70% of women rated their health condition as "bad." The incidence of illness after age 60 years was 77% among women and 61% among men. Most common were chest problems such as asthma, tuberculosis, and bronchitis. The percentage of unhealthy persons was slightly lower among illiterates and those with a university education than men and women with primary or middle school educational levels. These educational differences are presumed to reflect class-based occupational histories. In general, those with middle levels of education were employed in household industry or businesses with high exposure to disease. Men and women with unsatisfactory, conflictual family relationships also experienced increased health problems. Although respondents expressed the view that the shift from joint to nuclear family systems has lowered the status of the elderly, 62% maintained they did not need any further support from their families. A demand for some type of old age pension from the government was proposed, however. These findings suggest a need for increased social responsibility for the health and well-being of India's aging population.

Population growth under changed fertility schedule in stability conditions.

"This paper aims to investigate some models for population projection under a gradual change in fertility schedule, and to evaluate integrals therein for their actual values.... Some formulae for population projection have been derived under stability conditions. The proposed formulae are also illustrated with some numerical values of the parameters involved therein. The merits and shortcomings are also discussed." (SUMMARY IN FRE)

Estimation of fecundability of migrated couples in the process of rural out-migration in India.

"Based on a simple procedure developed by Menken (1979), the estimate of fecundability of migrated couples in the process of rural out-migration [in India] has been obtained in this paper. It is found that the estimates of fecundabilities for females of different age-groups are significantly larger than the level of fecundability estimated for non-migrated couples. Some possible explanations for observing such a large gap [are] given."

Some models for patterns of urbanization, migration and development.

"This paper aims to study the pattern of urbanization and the evolution of [the] relationship between rural-urban migration and the degree of economic development taking Gross National Product...into consideration. Intercensal age-specific rural net out-migration rates are also estimated from [tabulations] of the proportion of rural population of India by age through a recently developed procedure based on generalized stable population by Stupp (1989). A comparative study is also made between [the] survival column of India with a developed nation like Japan."

Commutation and migration: patterns, expectancies and consequences.

PIP: Data were derived from a 3-year prospective survey in India entitled Rural Development and Population Growth: A Sample Survey 1978 which analyzed 3 different types of villages with different phases of development. The pattern of commutation from the rural households was studied through a probability model. The commutation expectancy at birth and at older ages for semiurban villages (.82 moves/person) was higher in comparison to remote (.424 moves/person) and growth center (.405 moves/person) villages. The overall commutation expectancy from all 3 types of villages at birth and older ages was .585 moves/person. The expected number of moves was the highest for the 10-14 age group and for older ages in each of the 3 village types with 1.01, .519, and .496 moves per person for semiurban, remote, and growth-center villages, respectively. Commutation expectancy increased up to the 10-14 age group and after that gradually declined. Total mobility expectancy at birth and older ages for semiurban villages was 1.27 moves/person, again higher than for remote (1.08) and growth-center villages (1.06). Households with at least 1 migrant or households with both migrant(s) and commuter(s) owned better houses and they were better educated with a higher level of socioeconomic status in comparison to other types of households. Based on the characteristics of the observed data and commutation it is proposed that negative binomial distribution described the situation well.^ieng

A probability model for the distribution of the number of migrants at the household level.

PIP: A probability model to characterize the pattern of total number of migrants from a household has been developed. Earlier models which had several limitations have been improved. The assumptions of the proposed model were migrants from a household occur in clusters and may rarely happen, and the risk of migration occurring in a cluster vary from household to household. Data from 3514 households from either semiurban, remote, or growth center villages in India were applied to the proposed probability model. The Rural Development and Population Growth--A Sample Survey 1978 defined household as a group of people who normally live together and eat from a shared kitchen. The people do not necessarily reside in the village, however, but work elsewhere and send remittances. They consider themselves to be part of the household. Observed and expected frequencies significantly agreed only for those in the high social status group (p.05). The mean number of clusters/household was greater for remote villages (.26) than growth center and semiurban villages (.22 and .13, respectively). On the other hand, the mean number of migrants/cluster was smaller for remote villages (2.1) than growth center and semiurban villages (2.17 and 2.62, respectively). These results may indicate that men migrate alone in different clusters from remote villages and men from growth center and semiurban villages migrate with their families in fewer number of clusters. Men from growth center and semiurban villages tended to be well educated and professionals. The mean number of migrants/household was higher for remote villages (.56) than growth center (.47) and semiurban (.33) villages. Commuting to work accounted for this difference.^ieng

Socioeconomic factors and effect on fertility of husband-wife separation due to migration.

PIP: Socioeconomic characteristics of migrant and non-migrant couples from 19 villages in eastern Uttar Pradesh state, India were analyzed to explain the commonly reported lower fertility of migrants. In these communities, men migrate to cities for work, returning home intermittently. Data were taken from the Rural Development and Population Growth sample survey of 1978, encompassing 3514 households, in 19 remote, semi-urban and newly industrialized villages. Results from 35 castes, income levels and male educational levels were grouped into 5 levels for analysis. 83% of male migrants were married; of these 75% left their wives in the villages. The average number of children was 2.88 for migrant couples, and 3.81 for non-migrants. Generally lower castes had more children, with a linear shaped curve, with higher fertility for lowest and highest socioeconomic classes. Average number of children of both migrant and nonmigrant groups was lower in proportion to education of both spouses. There were few highly educated wives, and some of these with migrant husbands had atypically high fertility.^ieng

A probability model for the number of migrants.

PIP: The authors present a probability model to describe the pattern of dependent migrants per rural household in India. It is based on a compound distribution and is tested on the distribution of households according to the number of migrants.^ieng

On some probability models and their applications to the distribution of the number of migrants from a household.

This paper discusses some probability models in relation to their application to the distribution of the number of migrants from a household. 2 types of distribution of migrants from a household are described here: 1) male migrants aged 15 and above and 2) total number of migrants including females and children from a household. It is found that the model proposed here fitted the several sets of observed data on the number of migrants satisfactorily well.

On the distribution of distance associated with marriage migration in rural areas of Uttar Pradesh, India.

"This paper examines the relationship between marriage and migration distance through a probabilistic model with two parameters. The suitability of the present model is tested with several sets of observed data collected from the rural areas in 1978 in Eastern Uttar Pradesh, India; and it is found that the model fits the observed data reasonably well."

Determinants of rural-urban migration in India: a micro approach.

PIP: The author examines the determinants of rural-to-urban migration in India. Findings indicate that rural out-migration is most affected by the number of persons who had previously migrated from the same village, the distance from the village to the nearest large city or town and main road, the sex ratio of the village, and the educational level of its inhabitants. Data are from a 1984 survey.^ieng

Inter-generational occupational mobility and population heterogeneity: a statistical analysis.

"In the present paper an attempt is made to study the inter-generational occupational mobility in three types of developing villages [in India] that are heterogeneous in many socio-economic and other aspects. The specific objectives of this study are: (i) to study the overall occupational mobility of fathers-sons and to find out the predicted equilibrium structure, (ii) to find the waiting time (number of generations) that sons will stay in their fathers' occupational state before moving to other ones and (iii) to test the hypothesis of identical class structures in these three types of heterogeneous societies." The data are from a 1978 sample survey, and "the basic simple time-homogeneous Markov Chain model by Prais (1955) is employed...."

Trends in rural out-migration at household level.

PIP: The analysis of migration at micro-levels has important implications for local planning and for sociological models of communities, families and individuals. Trends in rural outmigration at the household level are studied using 1969-1970 Varanasi survey data. The negative binomial distribution is proposed to describe the pattern of household outmigration. The assumptions under which the distribution is obtained are delineated. For households of various sizes, the observed and expected frequencies are compared, demonstrating that the fitted distribution is a reasonable approximation.^ieng

A study of seasonal trends in delivery and medical termination of pregnancy.

PIP: Unlike some animals, there is no season for conception in human beings, yet a marked seasonal variation in the number of deliveries and medical termination of pregnancy has been observed in a study conducted in India. Data used for the analysis was taken from the records of the department of Obstetrics and Gynaecology and monthly data on deliveries were taken for 4 years and on MTP were taken for only 3 years. Medical termination of pregnancy had the highest index in the month of April and lowest in the month of November while indices of deliveries were maximum in August, September and October and minor in April, May and June. These findings show maximum number of conceptions occur during the winter months for obvious reasons and therefore the index of deliveries is likely to be maximum during months preceeding winter, i.e., August-October. As the medical termination of pregnancy is permitted only up to 20 weeks of gestation, the patients conceiving during winter months, November-February are likely to report for termination in early summer to late monsoon season.^ieng