Characteristics of larvae of the southwestern corn borer, Diatraea grandiosella, obtained from populations present in tropical and temperate regions

A comparative study was undertaken of southwestern corn borers (Diatraea grandiosella) collected from south central Mexico (19°N latitude) and southeast Missouri (37°N latitude). All the life stages of the Mexican insects were found to be larger or heavier, or both, than were those of the Missouri insects. Mexican larvae grew at a higher rate and attained a significantly heavier body weight than did Missouri larvae. Although both Mexican and Missouri larvae underwent ecdyses during diapause, Mexican larvae ecdysed more frequently than did the Missouri larvae at 23°C light:dark 12 h:12 h. Larvae that ecdysed most frequently did not necessarily spend longer in diapause. Electrophoresis of the fat body and haemolymph proteins of Mexican and Missouri larvae revealed similar patterns. The fat body of diapausing Mexican larvae contained substantial amounts of a diapause-associated protein which has been characterized previously from the fat body of Missouri Larvae. Double immunodiffusion confirmed that the diapause-associated protein of the Mexican larvae was identical to that present in the Missouri larvae. Smaller amounts of this protein appear to be present in the fat body of diapausing Mexican larvae than are present in that of diapausing Missouri larvae.     

Craniometric variation in the Americas

Craniofacial variation is investigated in Latin America and the Caribbean. The samples included in this study are two historic and one prehistoric sample from Ecuador; prehistoric and modern Cuban samples; a prehistoric Peruvian sample; two prehistoric Mexican samples and one contemporary admixed Mexican sample; a 16th/17th-century Spanish sample; and Terry blacks. Biological distance is investigated using traditional craniometrics by computing size and shape variables according to Mosimann and colleagues. This study shows that there is much biological variation within the Americas.     

The Role of Local Knowledge in Medical Practice: A Trans-historical Perspective

This article explores the role ofparticipant-observation and ethnographic writing inthe shaping of medical practice since Hippocrates. Drawing on a range of historical sources and genresthat include the 17th- and 18th-centurymedical topographies and medical geographies,19th-century medical ethnography and folklore,and their marginal persistence into the 20thcentury in the form of Mexican pasante reports,I argue that these writings should not be approachedas part of the history of anthropology, but asspecifically medical genres related to medicalpractice. The abandonment of these ethnographicpractices by modern biomedicine is, I conclude, aconsequence of two related developments: the hegemonyof clinical epistemology and the depersonalization anddepoliticization of physicians' commitment to theirpatients.To Eduardo L. Menéndez     

Relative lower extremity length in Mexican American and in American black and white youth

Stature, sitting height, estimated leg (subischial) length and the sitting height/stature ratio are compared in Mexican American, American White and American Black boys 9 through 14 years of age and girls 12 through 17 years of age. Mexican American youth are shorter in stature and have absolutely shorter lower extremities. The sitting height of Mexican American youth is similar to that of Black youth and shorter than that of White youth. The sitting height/stature ratio is virtually identical in Mexican American and White youth, indicating similar proportions of lower extremities to stature. In contrast, Black youth have absolutely and relatively longer lower extremities than Mexican American and White youth. These results would thus seem to suggest that reference data for the body mass index (BMI) based on American White youth can be used with Mexican American youth, while race-specific values may be necessary for American Black youth. However, ethnic variation in physique, perhaps frame size, may be a factor which should be more systematically considered in evaluating the utility of the body mass index.     

Seasonal changes in thermoregulation of the raccoon dog (Nyctereutes procyonoides Gray 1834)

Oxygen consumption (ml X kg-0.75/min) in relation to ambient temperature (Ta) in the raccoon dog whelps at the ages of 7-9 weeks and 17-19 weeks is described by equations y = 32.9-0.69x and y = 26.2-0.49x, respectively. The corresponding equations to adults in summer and winter pelages are y = 19.6-0.46x and y = 14.5-0.32x, respectively. The cooling constant (min-1) of deceased raccoon dogs decreased exponentially with increasing body mass, while M-0.75 specific heat transfer coefficient (W X kg-0.75/degrees C) regressed linearly on body mass, y = 0.124-0.00066x. Cooling rate of deceased animals were more dependent on body mass than on pelage quality.     

Lean, fat and bone masses are influenced by orchidectomy in the rat. A densitometric X-ray absorptiometric study

In man, hypogonadism is a risk factor for osteoporosis. Orchidectomy (ORX) in the rat leads to an imbalance between resorption and formation resulting in bone loss. We have measured whole body weight, lean and fat mass, whole bone mass (BMC) in the ORX rat model by dual X-ray densitometry (DXA). Forty-eight male Wistar rats (18-19 weeks old) were studied at 2, 4, 8 and 16 weeks. In each group, 6 rats were ORX and 6 sham-operated were used as control. DXA was performed on the whole body and isolated tibia. The whole body weight of the ORX animals became significantly decreased only at 16 weeks. Whole body BMC was reduced from 8 weeks in the ORX group. The most striking result was a net decrease in lean mass that reached -15.7% at 16 weeks. On the other hand, fat mass remained unchanged during the time series in the ORX animals.     

Positive correlation between the body weight of anestrous goats and their response to the male effect with sexually active bucks

In the present study, we analyzed the results of two years of response to the male effect in seasonally anestrous goats to investigate whether the activation of female reproductive activity by the male effect is related to the body weight of the females. Seventy-nine adult female Mexican mixed breed goats were used. The anestrous females were exposed during 15 days to sexually active males, and were classified into three categories according to their mean body weight +/-SD (42 +/- 9 kg) (Light: < or = 33 kg, n = 19; Medium: 34-50 kg, n = 46; Heavy: > or = 51 kg, n = 14). More than 98% of the goats from the Medium and Heavy groups showed at least one estrus behavior within the first 15 days following the introduction of the bucks, versus only 63% of the females from the Light group (P < 0.01). The interval between the introduction of the males and the onset of estrus behavior was longer in the females of the Light and Medium groups (4.2 +/- 0.8 and 3.3 +/- 0.3 days) than in the females of the Heavy group (2.0 +/- 0.2 days; P < 0.03). Also, body weight was negatively correlated with latency to first estrus (Spearman r = -0.57; P < 0.001). These results are in agreement with the hypothesis that the ability of anestrous goats to respond to the male effect is positively influenced by their body weight.     

The Impact of Antiretroviral Therapy in a Cohort of HIV Infected Patients Going in and out of the San Francisco County Jail

Background

Jails are an important venue of HIV care and a place for identification, treatment and referral for care. HIV infected inmates in the San Francisco County jail are offered antiretroviral treatment (ART), which many take only while in jail. We evaluated the effect of ART administration in a cohort of jail inmates going in and out of jail over a nine year period.

Methodology/Principal Findings

In this retrospective study, we examined inmates with HIV going in and out of jail. Inmates were categorized by patterns of ART use: continuous ART - ART both in and out of jail, intermittent ART - ART only in jail; never on ART - eligible by national guidelines, but refused ART. CD4 and HIV viral load (VL) were compared over time in these groups. Over a 9 year period, 512 inmates were studied: 388 (76%) on intermittent ART, 79 (15%) on continuous ART and 45(9%) never-on ART. In a linear mixed model analysis, inmates on intermittent ART were 1.43; 95%CI (1.03, 1.99) times and those never on ART were 2.89; 95%CI (1.71, 4.87) times more likely to have higher VL than inmates on continuous ART. Furthermore, Inmates on intermittent ART and never-on ART lost 1.60; 95%CI (1.06, 2.13) and 1.97; 95%CI (0.96, 3.00) more CD4 cells per month, respectively, compared to continuously treated inmates. The continuous ART inmates gained 0.67CD4 cells/month.

Conclusions/Significance

Continuous ART therapy in jail inmate''s benefits CD4 cell counts and control of VL especially compared to those who never took ART. Although jail inmates on intermittent ART were more likely to lose CD4 cells and experience higher VL over time than those on continuous ART, CD4 cell loss was slower in these inmates as compared to inmates never on ART. Further studies are needed to evaluate whether or not intermittent ART provides some benefit in outcome if continuous ART is not possible or likely.     

Evidence of a novel quantitative-trait locus for obesity on chromosome 4p in Mexican Americans

Although several genomewide scans have identified quantitative-trait loci influencing several obesity-related traits in humans, genes influencing normal variation in obesity phenotypes have not yet been identified. We therefore performed a genome scan of body mass index (BMI) on Mexican Americans, a population prone to obesity and diabetes, using a variance-components linkage analysis to identify loci that influence BMI. We used phenotypic data from 430 individuals (26% diabetics, 59% females, mean age +/- SD = 43 +/- 17 years, mean BMI +/- SD = 30.0 +/- 6.7, mean leptin (ng/ml) +/- SD = 22.1 +/- 17.1) distributed across 27 low-income Mexican American pedigrees who participated in the San Antonio Family Diabetes Study (SAFDS) for whom a 10-15-cM map is available. In this genomewide search, after accounting for the covariate effects of age, sex, diabetes, and leptin, we identified a genetic region exhibiting the most highly significant evidence for linkage (LOD 4.5) with BMI on chromosome 4p (4p15.1) at 42 cM, near marker D4S2912. This linkage result has been confirmed in an independent linkage study of severe obesity in Utah pedigrees. Two strong positional candidates, the human peroxisome proliferator-activated receptor gamma coactivator 1 (PPARGC1) and cholecystokinin A receptor (CCKAR) with major roles in the development of obesity, are located in this region. In conclusion, we identified a major genetic locus influencing BMI on chromosome 4p in Mexican Americans.     

Does size really matter? Weight and values in public health

The medical community has long regarded obesity and overweight as serious health risks, and popular culture reflects these concerns. A focus on body weight reduction motivates many contemporary exercise and diet practices, especially among women. Yet, there is significant evidence that those risks have been exaggerated, that weight loss regimens may be more detrimental to health than moderate obesity, and that pressure to be thin leads to disordered eating and unhealthy lifestyle choices. This paper examines the problematic manners in which some national health policies regard the problems of overweight and obesity. It contends that concepts of aesthetics, grounded in 19th-century beliefs about the body, guide clinicians to emphasize measurement of the body in health assessment at potential cost to individual wellness.     

Authorizing Knowledge in Science and Anthropology

An analogy exists between today's "defenders" of science in the "science/culture wars" and 19th-century "defenders" of euclidean geometry. Current critics have appointed themselves as arbiters of truth in a manner analogous to that of 19th-century mathematicians and theologians who argued against noneuclidean geometry that challenge Euclid's mathematically, philosophically, and theologically entrenched fifth postulate. The science wars then and now are not about science versus antiscience, objectivity versus subjectivity, but about authority in science: what kind of science should be practiced, and who gets to define it?     

Ethnic differences in anthropometric characteristics of young children and their parents

The distribution of body fat, or fat patterning, is an important risk factor for cardiovascular disease and diabetes, independent of obesity. Furthermore, the incidence of cardiovascular disease and diabetes varies by ethnicity. We documented ethnic differences in anthropometric characteristics and body fat distribution between Anglo, Black, and Mexican American men (n = 101), women (n = 245), boys (n = 111), and girls (n = 111). We used aggregates of skinfold measures to examine ethnic differences in the deposition of fat in body compartments (body, trunk, leg, and arm) and analyzed trunk-extremity skinfold ratios to determine which best reflected ethnic differences in fat distribution. The results show that Mexican American mothers have larger skinfold ratios and more body fat (as determined by skinfold aggregates) than either Anglo or Black American mothers, whereas Black American mothers have larger ratios than Anglo American mothers. Mexican American fathers also have larger skinfold ratios but not more body fat (skinfold aggregates) than Anglo American fathers. Mexican American fathers have more body fat than Black American fathers, but we found no differences between skinfold ratios. The ethnic differences among children in skinfold ratios and aggregates are similar to those found among fathers, with more differences among girls than boys. Fat patterning differences do exist among the three ethnicities, with greater trunk fat among Mexican and Black Americans. Those ethnicities are known to be at higher risk for cardiovascular disease and diabetes.     

The biological standard of living in 19th century Mexico and in the American West

During the mid-19th century, the United States acquired Texas and large parts of Mexican territory with the vast Mexican-born population. This paper considers the biological standard of living of the part of this population that was incarcerated in American prisons. We use their physical stature as a proxy for their biological welfare. These data confirm earlier results which showed that adult heights tended to stagnate in Mexico during the late-19th century despite considerable social and political turmoil. While there is some evidence of a decline in height among youth, the decline is slight (<1 cm). As in other 19th century samples, farmers were the tallest. Americans were taller than Mexican prisoners by about 2 cm.     

Culturally Determined Patterns of Violence: Biological Anthropological Investigations at a Historic Urban Cemetery

Patterns of violence and the type and distribution of resulting injuries are highly culturally specific. In this study, skeletal data from a historic cemetery (St. Martin's, England) are combined with contemporary sources and modern clinical data to enable the patterning of violence-related injuries to be interpreted. Particular consideration was given to the possibility of a relationship between commonly occurring types of violence and those that are popular in sport. Phillip Walker (1997) suggested that the growth of fist fighting in the early-20th-century United States was stimulated by the rising popularity of boxing. At St. Martin's, a pattern of injuries consistent with fighting in a style specific to boxing is evident, suggesting that developing boxing styles were influential in 18th- and 19th-century Britain as the accepted way of settling interpersonal disputes. This research underlines the importance of interpreting skeletal data in their specific cultural context to gain the maximum information on patterns of behavior.     

Differences in skeletal and muscle mass with aging in black and white women

Previous cross-sectional studies using delayed gamma neutron activation analysis and whole body counting suggested that the relationship of total body calcium (TBCa) to total body potassium (TBK) (muscle mass, body cell mass) remained constant with age. This led to the hypothesis that the muscle mass and skeletal mass compartments are integrated in their response to aging. It had also been hypothesized that loss of skeletal and muscle mass was similar between races. In the current study, delayed gamma neutron activation analysis and whole body counting were performed on 90 black and 143 white women 20-69 yr of age. Black women had higher TBCa and TBK values than white women, even when the data were adjusted for age, height, and weight. TBCa was correlated with height and TBK with weight. The estimated decline of skeletal mass (TBCa) from 20 to 70 yr was 18% in black women and 19% in white women. However, the lifetime decline of TBK was only 8% for black women, compared with 22% for white women. Black women may lose TBK more slowly than TBCa with aging, compared with white women. In particular, correlation of TBCa and age was similar for blacks and whites (r = -0.44 and r = -0.54, respectively). However, for TBK these correlations were r = -0.14 and r = -0.42. These data confirm a higher musculoskeletal mass in black women and suggest that the loss of muscle mass with age may be lower in black than in white women. These ethnic differences do not support the hypothesis of an integrated musculoskeletal system, so that these two components should be considered separately. A prospective study is needed to confirm these findings.     

Reproductive compatibility and mitochondrial DNA restriction site analysis of New World screwworm, Cochliomyia hominivorax, from North Africa and Central America

The reproductive compatibility of New World screwworms, Cochliomyia hominivorax (Coquerel), from North Africa and a strain being mass produced for the Mexican eradication programme was examined to assess the feasibility of using flies from the Mexican screwworm mass production facility for a sterile insect technique eradication programme in North Africa. Males from the production strain mated randomly with females from North Africa and from the production strain when both were present. Neither strain of males discriminated between cuticular extracts of North African and production strain females containing a contact sex pheromone. Interstrain crosses between North African flies and production flies were fertile and produced fertile progeny. Chromosome morphology did not differ significantly between the two strains and homologue pairing was normal in hybrid meiotic and polytene nuclei. Mitochondrial DNA restriction site analyses indicated that the genetic divergence of the North African strain from Mexican and Central American strains was within the range of the diversity observed in Central American, Mexican and Caribbean populations. Test results indicate that New World screwworms from North Africa are reproductively compatible with the strain currently being mass produced in Mexico. Mating barriers should not impede the progress of an eradication programme using the sterile insect technique in North Africa with sterile screwworms from the Mexican mass production facility.     

Parental mass change and food provisioning in Adélie penguins rearing chicks in colonies with contrasting sea-ice conditions

Adélie penguins (Pygoscelis adeliae) changed the pattern of energy allocation for self-maintenance and food provisioning among three colonies. Parents made longer trips (44-57 h) at Davis, where they foraged in open waters, than in Syowa (17-22 h) where fast sea-ice remained. Those at Dumont d'Urville, where the sea-ice disappeared in mid-summer, made trips of variable duration (22-41 h). During foraging trips, parents at Davis accumulated a greater amount of body tissue (0.40 kg) than parents at other locations (-0.06 to 0.13 kg) to offset the loss of body tissue during previous chick guarding. As a consequence, parents at these colonies had a similar body-mass decrease rate throughout the chick-rearing period (10-19 g/day). Parents with a smaller departure body mass seemed to make longer trips at Davis and Dumont d'Urville, and those making longer trips seemed to accumulate more body tissue at Davis, though these effects were not observed at Syowa. Stomach-content mass was greater at Davis (457 g) and Dumont d'Urville (551 g) than at Syowa (271-363 g), while the frequency of colony visits with meals was smaller at Davis (0.31/day per bird) and Dumont d'Urville (0.39/day per bird) than at Syowa (0.64-0.68/day per bird). Stomach-content mass was independent of trip duration. We propose the hypothesis that parents maintain their own body condition by regulating the accumulation of body tissue during foraging trips but change food provisioning with respect to variable foraging-trip duration.     

Genotype Analysis of Hepatitis C Virus among Blood Donors and Inmates in Metro Manila,The Philippines

Antibodies against hepatitis C virus (HCV) were detected in 18 (2.3%) of 800 sera from commercial blood donors and 23 (4.6%) of 502 sera from inmates in Metro Manila, the Philippines. The difference in the antibody prevalence between the two groups was statistically significant (P<0.05). HCV RNA was detected in 14 (78%) of the 18 antibody-positive sera from blood donors and 19 (83%) of the 23 antibody-positive sera from inmates. Genotype analysis revealed that HCV-1b (50%) was most common among blood donors, followed by HCV-1a (36%) and HCV-2a (7%). Among inmates, on the other hand, HCV-1a (68%) was most common, followed by HCV-1b (11%), HCV-2a (5%) and HCV-2b (5%). Overall, HCV-1a and HCV-1b appeared to be predominant among them. Thus, the genotype prevalence in the Philippines was distinct from those in other Southeast Asian countries such as Thailand, Vietnam and Indonesia, and also distinct from those in the Far East including Taiwan, Mainland China and Japan.     

Prevalence and correlates of hepatitis C virus infection among inmates entering the California correctional system

To estimate the prevalence and predictors of hepatitis C virus (HCV) infection among inmates, a cross-sectional survey was conducted in 1994 among inmates entering six reception centers of the California Department of Corrections. Discarded serum samples were tested for antibodies to human immunodeficiency virus (HIV), HCV, hepatitis B core, and hepatitis B surface antigen (HBsAg). Of 4,513 inmates in this study, 87.0% were men and 13.0% were women. Among male inmates, 39.4% were anti-HCV-positive; by race/ethnicity, prevalences were highest among whites (49.1%). Among female inmates, 53.5% were anti-HCV-positive; the prevalence was highest among Latinas (69.7%). In addition, rates for HIV were 2.5% for men and 3.1% for women; and for HBsAg, 2.2% (men) and 1.2% (women). These data indicate that HCV infection is common among both men and women entering prison. The high seroprevalence of anti-HCV-positive inmates may reflect an increased prevalence of high-risk behaviors and should be of concern to the communities to which these inmates will be released.     

Variation in plasma leptin levels in response to fasting in Antarctic fur seals (Arctocephalus gazella)

Plasma leptin levels were determined in 8 lactating female and 20 pup Antarctic fur seals (Arctocephalus gazella) during fasting periods of normal duration. Plasma leptin levels ranged from 1.35 3.19 ng x ml(-1) in lactating females and 1.79-4.80 ng x ml(-1) in pups and were not positively correlated with body mass or condition. A negative trend, however, was observed between plasma leptin levels and body condition in lactating females upon their arrival at the colony following a foraging trip (beginning of fast). In accordance with findings in other species, plasma leptin levels dropped significantly (P < 0.02) in response to the 17-19% drop in body mass experienced by pups during fasting. In contrast, plasma leptin levels in lactating females increased during the first 24 h of fasting before decreasing throughout the remaining 48 h of the fast. This unexpected result could be due to the high level of energy expenditure by seals as they swim back to the colony (i.e. post-exercise response) or may be influenced by the intense suckling activity experienced by females during the onshore fasting periods. The results of this study support recent findings in other carnivore species which suggest the primary physiological role of leptin in these species may not necessarily be as a signal of the magnitude of body energy reserves.