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1.
J Evol Biol ; 30(5): 889-897, 2017 05.
Article in English | MEDLINE | ID: mdl-28267227

ABSTRACT

Natural selection presumably conserved mechanisms that allow females to block or terminate gestation when environmental circumstances threaten the survival of offspring. One example of this adaptive reproductive suppression, the Bruce effect, has been identified in several species, both in the laboratory and in the wild. Although descriptive epidemiology reports low fertility among women experiencing stressful circumstances, attempts to detect a Bruce effect in humans have been rare and limited. We contribute to this limited work by examining the relationship between the odds of child death and the sex ratio at birth in Sweden for the years 1751-1840. We find evidence of a generalized Bruce effect in humans in that unexpected changes in child mortality predict opposite unexpected changes in the secondary sex ratio in the following year, even after adjusting for period life expectancy. Our analysis broadens the scope of the Bruce effect literature to include humans, suggesting that women, through noncognitive decisional biology, adjust reproductive strategies and investments in response to changing environmental conditions.


Subject(s)
Child Mortality , Fertility , Sex Ratio , Adult , Child , Environment , Female , History, 18th Century , History, 19th Century , Humans , Pregnancy , Reproduction , Sweden
2.
Am J Hum Biol ; 27(3): 426-31, 2015.
Article in English | MEDLINE | ID: mdl-25382092

ABSTRACT

OBJECTIVES: Human conception cohorts in gestation during stressful times reportedly yield lower ratios of male to female live births than do other conception cohorts. Much literature attributes this phenomenon to spontaneous abortion of less fit male fetuses. Controversy remains, however, as to whether stressful times make males fetuses less fit ("Shifting Distribution" of fitness) or whether male fetuses need greater fitness to avoid spontaneous abortion during stressful times ("Shifting Criterion" for survival). METHODS: Although research using gestational hCG as a signal of fetal fitness reports support for the latter mechanism, we believe an analytic error casts doubt on those findings. Here we offered an alternative test that corrects the error. CONCLUSION: This more accurate test found similar results to those originally reported.


Subject(s)
Abortion, Spontaneous/metabolism , Chorionic Gonadotropin/blood , Fetus , Models, Theoretical , Sex Ratio , Cohort Studies , Female , Humans , Male , Pregnancy , Stress, Psychological/metabolism
3.
Am J Hum Biol ; 24(4): 526-32, 2012.
Article in English | MEDLINE | ID: mdl-22411168

ABSTRACT

OBJECTIVES: Antagonists in the debate over whether the maternal stress response during pregnancy damages or culls fetuses have invoked the theory of selection in utero to support opposing positions. We describe how these opposing arguments arise from the same theory and offer a novel test to discriminate between them. Our test, rooted in reports from population endocrinology that human chorionic gonadotropin (hCG) signals fetal fitness, contributes not only to the debate over the fetal origins of illness, but also to the more basic literature concerned with whether and how natural selection in utero affects contemporary human populations. METHODS: We linked maternal serum hCG measurements from prenatal screening tests with data from the California Department of Public Health birth registry for the years 2001-2007. We used time series analysis to test the association between the number of live-born male singletons and median hCG concentration among males in monthly gestational cohorts. RESULTS: Among the 1.56 million gestations in our analysis, we find that median hCG levels among male survivors of monthly conception cohorts rise as the number of male survivors falls. RESULTS: Elevated median hCG among relatively small male birth cohorts supports the theory of selection in utero and suggests that the maternal stress response culls cohorts in gestation by raising the fitness criterion for survival to birth.


Subject(s)
Abortion, Spontaneous/etiology , Chorionic Gonadotropin/blood , Fetal Death/etiology , Selection, Genetic , Sex Ratio , Abortion, Spontaneous/epidemiology , Birth Rate , California/epidemiology , Cohort Studies , Female , Fetal Death/epidemiology , Genetic Fitness , Humans , Infant Mortality/trends , Infant, Newborn , Live Birth , Male , Models, Biological , Pregnancy , Stress, Physiological , Survival Analysis , Time Factors
4.
J Rural Health ; 16(3): 224-9, 2000.
Article in English | MEDLINE | ID: mdl-11131762

ABSTRACT

Rural hospitals have used numerous strategies over the past several decades to recruit and retain physicians. These have included providing physicians economic incentives, immigration status, professional and technical support and establishing rural training tracks (RTT) in family practice residency programs. This paper presents the experience of an isolated rural region in southwestern New York state that has employed each of these strategies in the past decade. Success as measured by the change in size of the medical staff, hospital operating margins, admissions and employment occurred only after the emphasis changed from meeting hospital needs to physician needs. Pivotal to this strategy was the nurturing and development of an RTT. Investment in the residency program required strong leadership to ensure the political, financial and operational commitment of its affiliated hospital. In addition, the RTT required an affiliation with a financially viable, full-service hospital, a strong on-site chief of service, family physicians who performed cesarean sections, midlevel providers and practitioners dedicated to the mission of teaching.


Subject(s)
Family Practice/education , Hospitals, Rural/organization & administration , Internship and Residency/organization & administration , Medically Underserved Area , Models, Educational , Career Choice , Hospital Bed Capacity, 100 to 299 , Hospitals, Rural/statistics & numerical data , Humans , Investments , Leadership , New York , Organizational Case Studies , Physician Incentive Plans , Professional Practice Location , Program Evaluation , Workforce
5.
Am J Public Health ; 89(6): 851-5, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10358674

ABSTRACT

OBJECTIVES: This study sought, first, to explain and reconcile the provocation and inhibition theories of the effect of rising unemployment on the incidence of antisocial behavior. Second, it tested the hypothesis, implied by the provocation and inhibition theories, that the relationship between unemployment and foster home placements forms an inverted "U." METHODS: The hypothesis was tested with data from California for 137 months beginning in February 1984. RESULTS: Findings showed that the hypothesis was supported. CONCLUSIONS: Rising joblessness increases the incidence of foster home placements among families that lose jobs or income. Levels of joblessness that threaten workers who remain employed, however, inhibit antisocial behavior and reduce the incidence of foster home placements. This means that accounting for the social costs of unemployment is more complicated than assumed under the provocation theory.


Subject(s)
Family/psychology , Foster Home Care/statistics & numerical data , Social Behavior Disorders/psychology , Stress, Psychological/psychology , Unemployment/psychology , Unemployment/statistics & numerical data , Adaptation, Psychological , Adult , California , Child , Female , Foster Home Care/trends , Humans , Incidence , Male , Prevalence , Psychological Theory , Risk Factors , Seasons , Social Behavior Disorders/etiology , Social Behavior Disorders/prevention & control , Stress, Psychological/etiology , Stress, Psychological/prevention & control , Unemployment/trends
6.
Am J Public Health ; 88(4): 586-9, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9550999

ABSTRACT

OBJECTIVES: The objective of this study was to test the hypothesis that unexpectedly high unemployment in a community is associated with reduced odds that registered breast tumors are local. METHODS: The hypothesis was tested with data from San Francisco for the 132 months beginning with January 1983. RESULTS: Registered breast tumors were less likely to be local during periods of unexpectedly high unemployment (8% less likely among non-Hispanic White women and 24% less likely among African-American women). CONCLUSIONS: Job loss may restrict access to health services. Fear of job loss may also distract women from breast self-examination and the identification of suspicious breast signs.


Subject(s)
Breast Neoplasms/epidemiology , Breast Neoplasms/prevention & control , Unemployment/statistics & numerical data , Women, Working/statistics & numerical data , Black or African American/statistics & numerical data , Breast Neoplasms/pathology , Fear , Female , Health Services Accessibility , Humans , Neoplasm Staging , Odds Ratio , SEER Program , San Francisco/epidemiology , Unemployment/trends , White People/statistics & numerical data
7.
J Health Soc Behav ; 37(4): 381-7, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8997892

ABSTRACT

Persons believed to be mentally ill and imminently violent are often subjected to coerced treatment. Among the justifications for this practice is the argument that removing such people from the community is analogous to quarantine. We test the quarantine theory using daily data from San Francisco. Results suggest that the incidence of coerced treatment of males is inversely related to assaults and batteries by males one day later. The finding implies that persons who are involuntarily committed are at elevated risk of violent behavior. The implications of the findings for the prevention of assaultive behavior are briefly described.


Subject(s)
Commitment of Mentally Ill , Violence/prevention & control , Algorithms , Coercion , Female , Humans , Male , Risk Factors , San Francisco , Time Factors , Violence/statistics & numerical data
8.
Article in English | MEDLINE | ID: mdl-7752030

ABSTRACT

Because of serious side effects, the indications for intralesional steroid injection of adnexal hemangiomas are unclear. Of 23 children with such lesions who were examined over a period of 9 years, 9 had no evidence of amblyopia and needed no intervention. Five required steroids intralesionally and/or systemically because of threatened occlusion of the pupillary axis. The remaining 9 were considered at risk of anisometropic amblyopia because of induced astigmatism: 5 received injections and 4 were treated with glasses and/or patching alone. The visual, refractive, and cosmetic results of the injected and conservatively managed anisometropes were similar. We recommend that steroid injection be reserved for patients with threatened occlusion of the visual axis and for those with severe astigmatism or amblyopia refractory to conservative management.


Subject(s)
Amblyopia/therapy , Anisometropia/therapy , Betamethasone/therapeutic use , Eyelid Neoplasms/drug therapy , Hemangioma, Capillary/drug therapy , Triamcinolone/therapeutic use , Amblyopia/etiology , Anisometropia/etiology , Drug Therapy, Combination , Eyeglasses , Eyelid Neoplasms/complications , Hemangioma, Capillary/complications , Humans , Infant , Injections, Intralesional , Refraction, Ocular , Sensory Deprivation , Visual Acuity
9.
Pediatr Clin North Am ; 40(4): 827-39, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8345969

ABSTRACT

A disproportionate share of ocular and orbital injuries occur in children. This article reviews the evaluation and initial management of ocular trauma and chemical burns to the eye. Traumatic conditions are classified according to the particular area of the eye or orbit involved; chemical burns constitute a separate section. Sports-related injuries and their prevention are emphasized.


Subject(s)
Eye Injuries/prevention & control , Athletic Injuries/prevention & control , Burns, Chemical/therapy , Child , Eye Burns/chemically induced , Eye Burns/therapy , Eye Injuries/diagnosis , Eye Injuries/therapy , Humans , Male
10.
Am J Ophthalmol ; 114(5): 575-8, 1992 Nov 15.
Article in English | MEDLINE | ID: mdl-1443018

ABSTRACT

We examined 30 infants in whom cortical visual impairment was diagnosed during their first year of life to ascertain prognostic factors for the development of object vision, defined as the ability to recognize faces or hand-held toys. All patients were followed up for a minimum of 12 months. The most common causes of cortical visual impairment in the 30 infants were hydrocephalus in nine infants (30.0%), birth asphyxia or neonatal hypoxia in eight infants (26.7%), intracranial hemorrhage with or without hydrocephalus in seven infants (23.3%), and meningitis in five infants (16.7%). Lack of development of object vision was associated only with hypoxia (P = .013). Findings on ophthalmic examination, an abnormality in the visual pathway on computed tomographic or magnetic resonance scan, and seizures, hydrocephalus, intracranial hemorrhage, meningitis, cerebral palsy, developmental delay, prematurity, microcephaly, and hearing deficit, did not appear to be risk factors for the lack of development of object vision.


Subject(s)
Form Perception/physiology , Vision Disorders/physiopathology , Visual Cortex/physiopathology , Brain Diseases/complications , Brain Diseases/physiopathology , Female , Follow-Up Studies , Humans , Infant , Male , Prognosis , Risk Factors , Vision Disorders/etiology
12.
Ophthalmology ; 98(5): 670-4, 1991 May.
Article in English | MEDLINE | ID: mdl-2062500

ABSTRACT

Glaucoma after pediatric cataract surgery, once well recognized, now occurs only rarely after modern lensectomy/vitrectomy. The authors performed directed glaucoma evaluations of 34 eyes of 26 children. Based on intraocular pressures of 26 mmHg or greater, glaucoma was diagnosed in 8 (24%) eyes of 7 (27%) children. Glaucoma was found more commonly among children followed more than 60 months and was diagnosed up to 105 months after surgery. Typically, the glaucoma was open angle and asymptomatic. Four children had had previously normal pressures recorded. With longer follow-up, it is likely that more children will be diagnosed with glaucoma after lensectomy/vitrectomy procedures. The authors believe such patients should be followed as glaucoma suspects for the rest of their lives.


Subject(s)
Cataract Extraction/adverse effects , Glaucoma, Open-Angle/etiology , Vitrectomy/adverse effects , Child , Child, Preschool , Follow-Up Studies , Glaucoma, Open-Angle/diagnosis , Humans , Infant , Infant, Newborn , Intraocular Pressure , Visual Fields
13.
Am J Ophthalmol ; 111(1): 71-6, 1991 Jan 15.
Article in English | MEDLINE | ID: mdl-1985494

ABSTRACT

We treated seven patients with unilateral oculomotor nerve palsy by transposition of the insertion of the superior oblique tendon to a point anterior and medial to the insertion of the superior rectus muscle without trochleotomy (Scott procedure). Additionally, large recessions of the lateral rectus muscle of involved eyes and, occasionally, recess/resect procedures of horizontal recti muscles of non-involved eyes were performed. All patients were followed up between one and eight years. Orthophoria in the primary position was achieved and maintained with one operation in four patients. A fifth patient had only a small residual exotropia. In two patients who had aberrant regeneration of the oculomotor nerve, surgery on horizontal recti muscles of the noninvolved eye improved the eyelid position of the involved eye after three operations.


Subject(s)
Oculomotor Nerve Diseases/surgery , Blepharoptosis/surgery , Child , Exotropia/surgery , Eyelids/surgery , Follow-Up Studies , Humans , Nerve Regeneration , Oculomotor Muscles/surgery , Prognosis
17.
Ophthalmology ; 97(9): 1166-75, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2234849

ABSTRACT

Clinical findings as well as eye and head movement recordings were analyzed from 23 patients with spasmus nutans without central nervous system (CNS) changes, 10 patients with spasmus nutans-like disease (head nodding, intermittent nystagmus associated with intracranial anomalies or visual pathway disorders), and 25 patients with infantile nystagmus. Ten diagnostic signs were established to differentiate between the patient groups. Although they were helpful in separating patients with infantile nystagmus from those with spasmus nutans, no difference was found between the patients with spasmus nutans with and without CNS lesions. This study indicates that eye and head movement recordings do not allow differentiation between benign spasmus nutans and spasmus nutans-like disease. The differentiation must be made on the basis of neuroimaging.


Subject(s)
Nystagmus, Pathologic/diagnosis , Spasms, Infantile/diagnosis , Child , Child, Preschool , Diagnosis, Differential , Eye Movements , Female , Head , Humans , Infant , Male , Posture
18.
Am J Ophthalmol ; 110(3): 300-2, 1990 Sep 15.
Article in English | MEDLINE | ID: mdl-2396656

ABSTRACT

Five children (three girls and two boys, aged 3 1/2 to 9 1/2 years) were referred by their pediatricians for evaluation of intermittent pulling on their eyelids. All the children were free of systemic disease. One child wore spectacles for accommodative esotropia but no child had evidence of an acute ocular disorder. The duration of symptoms before examination ranged from one to 13 months. None of the parents were able to identify temporally related stressful events. Reassurance alone was given to both parents and children; eyelid pulling resolved in all cases within two weeks. In only the youngest patient did eyelid pulling recur and no child developed other symptoms during a follow-up of six to 15 months. Following resolution, parents believed their children pulled on the eyelids to gain attention or because their eyes were initially irritated and they then developed a "bad habit." Children said they did it to "look funny" or because their "eyes were not opening enough."


Subject(s)
Child Behavior , Eyelids , Attention , Attitude to Health , Child , Child, Preschool , Female , Humans , Male , Parents
20.
Am J Ophthalmol ; 110(1): 28-32, 1990 Jul 15.
Article in English | MEDLINE | ID: mdl-2142382

ABSTRACT

Of five children who had Down's syndrome with optic nerve head elevation, without associated intracranial lesions, three underwent enhanced computed tomography for which no abnormalities were found. Partial, complete, or intermittent resolution of the optic disk elevation occurred in three children. In none of the children were retinal vessel dilation, splinter hemorrhages, optic nerve drusen, subsequent optic atrophy, or apparent visual loss noted. All of the children were hyperopic, but only one child had a hyperopia of greater than 3.50 diopters.


Subject(s)
Down Syndrome/pathology , Optic Disk/pathology , Child, Preschool , Down Syndrome/complications , Down Syndrome/physiopathology , Edema/complications , Edema/pathology , Female , Humans , Infant , Male , Optic Nerve Diseases/complications , Optic Nerve Diseases/pathology , Retinal Vessels/pathology , Vision, Ocular
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