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1.
Science ; 371(6533): 1042-1045, 2021 03 05.
Article in English | MEDLINE | ID: mdl-33674492

ABSTRACT

Uncertainty remains regarding the role of anthropogenic climate change in declining insect populations, partly because our understanding of biotic response to climate is often complicated by habitat loss and degradation among other compounding stressors. We addressed this challenge by integrating expert and community scientist datasets that include decades of monitoring across more than 70 locations spanning the western United States. We found a 1.6% annual reduction in the number of individual butterflies observed over the past four decades, associated in particular with warming during fall months. The pervasive declines that we report advance our understanding of climate change impacts and suggest that a new approach is needed for butterfly conservation in the region, focused on suites of species with shared habitat or host associations.


Subject(s)
Butterflies , Extinction, Biological , Global Warming , Animals , Conservation of Natural Resources , Ecosystem , Population Density , Seasons , United States
2.
Proc Biol Sci ; 287(1931): 20200922, 2020 07 29.
Article in English | MEDLINE | ID: mdl-33043867

ABSTRACT

Most of the world's crops depend on pollinators, so declines in both managed and wild bees raise concerns about food security. However, the degree to which insect pollination is actually limiting current crop production is poorly understood, as is the role of wild species (as opposed to managed honeybees) in pollinating crops, particularly in intensive production areas. We established a nationwide study to assess the extent of pollinator limitation in seven crops at 131 locations situated across major crop-producing areas of the USA. We found that five out of seven crops showed evidence of pollinator limitation. Wild bees and honeybees provided comparable amounts of pollination for most crops, even in agriculturally intensive regions. We estimated the nationwide annual production value of wild pollinators to the seven crops we studied at over $1.5 billion; the value of wild bee pollination of all pollinator-dependent crops would be much greater. Our findings show that pollinator declines could translate directly into decreased yields or production for most of the crops studied, and that wild species contribute substantially to pollination of most study crops in major crop-producing regions.


Subject(s)
Agriculture , Crops, Agricultural , Pollination , Animals , Bees , Food Supply , United States
3.
Ecol Appl ; 28(7): 1924-1934, 2018 10.
Article in English | MEDLINE | ID: mdl-30184292

ABSTRACT

Wild bee populations have undergone declines in recent years across much of the Western world, and these declines have the potential to limit yield in pollination-dependent crops. Highbush blueberry, Vaccinium corymbosum, and tart cherry, Prunus cerasus, are spring-blooming crops that rely on the movement of pollen by bees and other insects for pollination. Wild bee populations can be increased on farmland by providing floral resources, but whether the addition of these plants translates into increased pollinator density on crop flowers has not been documented in most cropping systems. To determine the importance of providing additional floral resources for wild bee pollinator communities, we selected blueberry fields and tart cherry orchards with and without herbaceous floral enhancements in western Michigan, USA. The bee communities visiting crop flowers, enhancements and control grassy field margins were sampled over a 5-yr period. In addition, the pollen diets of the most abundant wild bee crop pollinators were quantified across Michigan to better understand their foraging niches and to identify potentially important alternative host plants. The presence of floral enhancements did not increase the abundance of wild bees on either blueberry or cherry flowers during bloom. The bee community visiting blueberry was evenly composed of short-season bees that fly only during the spring and long-season bees that fly in both spring and summer. In contrast, the bee community visiting cherry was dominated by short-season spring bees. The majority of pollen collected by the wild bee communities visiting blueberry and cherry was from spring-flowering woody plants, with limited use of the herbaceous enhancements. Enhancements attracted greater abundance and species richness of bees compared to control areas, including twice as many floral specialists. Conserving summer-flying, grassland-associated bees is an appropriate goal for pollinator conservation programs. However, herbaceous enhancements may not provide adequate resources for the wild bees that pollinate spring-flowering crops. This study demonstrates that an examination of the pollen collected by wild bees across their flight periods can identify plant species to help them persist in intensively managed landscapes.


Subject(s)
Bees/physiology , Biodiversity , Diet , Plants , Pollen , Animals , Crops, Agricultural , Feeding Behavior , Flowers , Michigan , Seasons
4.
Arthropod Plant Interact ; 12(1): 21-29, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29430259

ABSTRACT

Plants have evolved many defenses against insect herbivores, including numerous chemicals that can reduce herbivore growth, performance, and fitness. One group of chemicals, the tropane alkaloids, is commonly found in the nightshade family (Solanaceae) and has been thought to reduce performance and fitness in insects. We examined the effects of the tropane alkaloid scopolamine, the alkaloid constituent of Datura wrightii, which is the most frequent host plant for the abundant and widespread insect herbivore Manduca sexta in the southwestern United States. We exposed caterpillars of two different species to scopolamine: M. sexta, which has a shared evolutionary history with Datura and other solanceous plants, and Galleria mellonella, which does not. We showed that the addition of ecologically-realistic levels of scopolamine to both the diet and the hemolymph of these two caterpillar species (M. sexta and G. mellonella) had no effect on the growth of either species. We also showed that M. sexta has no behavioral preference for or against scopolamine incorporated into an artificial diet. These results are contrary to other work showing marked differences in performance for other insect species when exposed to scopolamine, and provide evidence that scopolamine might not provide the broad-spectrum herbivore resistance typically attributed to it. It also helps to clarify the coevolutionary relationship between M. sexta and one of its main host plants, as well as the physiological mechanism of resistance against scopolamine.

5.
J Helminthol ; 91(3): 267-277, 2017 May.
Article in English | MEDLINE | ID: mdl-27240605

ABSTRACT

The successful use of helminths as therapeutic agents to resolve inflammatory disease was first recorded 40 years ago. Subsequent work in animal models and in humans has demonstrated that the organisms might effectively treat a wide range of inflammatory diseases, including allergies, autoimmune disorders and inflammation-associated neuropsychiatric disorders. However, available information regarding the therapeutic uses and effects of helminths in humans is limited. This study probes the practices and experiences of individuals 'self-treating' with helminths through the eyes of their physicians. Five physicians monitoring more than 700 self-treating patients were interviewed. The results strongly support previous indications that helminth therapy can effectively treat a wide range of allergies, autoimmune conditions and neuropsychiatric disorders, such as major depression and anxiety disorders. Approximately 57% of the self-treating patients observed by physicians in the study had autism. Physicians reported that the majority of patients with autism and inflammation-associated co-morbidities responded favourably to therapy with either of the two most popular organisms currently used by self-treaters, Hymenolepis diminuta and Trichuris suis. However, approximately 1% of paediatric patients experienced severe gastrointestinal pains with the use of H. diminuta, although the symptoms were resolved with an anti-helminthic drug. Further, exposure to helminths apparently did not affect the impaired comprehension of social situations that is the hallmark of autism. These observations point toward potential starting points for clinical trials, and provide further support for the importance of such trials and for concerted efforts aimed at probing the potential of helminths, and perhaps other biologicals, for therapeutic use.


Subject(s)
Biological Therapy/methods , Hymenolepis diminuta/growth & development , Inflammation/therapy , Self Administration/methods , Trichuris/growth & development , Animals , Humans , Treatment Outcome
6.
Oecologia ; 179(4): 1159-71, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26298191

ABSTRACT

Insect carnivores frequently use olfactory cues from plants to find prey or hosts. For plants, the benefits of attracting parasitoids have been controversial, partly because parasitoids often do not kill their host insect immediately. Furthermore, most research has focused on the effects of solitary parasitoids on growth and feeding of hosts, even though many parasitoids are gregarious (multiple siblings inhabit the same host). Here, we examine how a gregarious parasitoid, the tachinid fly Drino rhoeo, uses olfactory cues from the host plant Datura wrightii to find the sphingid herbivore Manduca sexta, and how parasitism affects growth and feeding of host larvae. In behavioral trials using a Y-olfactometer, female flies were attracted to olfactory cues emitted by attacked plants and by cues emitted from the frass produced by larval Manduca sexta. M. sexta caterpillars that were parasitized by D. rhoeo grew to lower maximum weights, grew more slowly, and ate less of their host plant. We also present an analytical model to predict how tri-trophic interactions change with varying herbivory levels, parasitization rates and plant sizes. This model predicted that smaller plants gain a relatively greater benefit compared to large plants in attracting D. rhoeo. By assessing the behavior, the effects of host performance, and the variation in ecological parameters of the system, we can better understand the complex interactions between herbivorous insects, the plants they live on and the third trophic level members that attack them.


Subject(s)
Datura/physiology , Diptera , Herbivory , Manduca/physiology , Odorants , Parasites , Animals , Datura/metabolism , Ecology , Female , Larva , Manduca/growth & development , Manduca/parasitology , Pheromones/metabolism , Smell
7.
Diabetes Obes Metab ; 13(12): 1105-13, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21733060

ABSTRACT

AIMS: Davalintide is a second-generation amylinomimetic peptide possessing enhanced pharmacological properties over rat amylin to reduce food intake in preclinical models. The current experiments in rats describe additional glucoregulatory actions of davalintide consistent with amylin agonism, and explore the duration of action of these effects. METHODS: Subcutaneous (SC) injection of davalintide slowed gastric emptying with equal potency to amylin (ED50's = 2.3 and 4.1 µg/kg). This effect was maintained for 8 h with davalintide, but not amylin. Intraperitoneal injection of davalintide also reduced food intake with a potency similar to amylin (ED50's = 5.0 and 11.3 µg/kg). Consistent with amylin agonism, davalintide (10 µg/kg, SC) suppressed the plasma glucagon response over 90 min following an intravenous arginine bolus in anaesthetized rats. The elimination t(½) of davalintide (200 µg/kg, SC) was 26 min, similar to the t(½) of amylin, suggesting that pharmacokinetic-independent mechanisms contribute to davalintide's enhanced duration of action. Binding kinetic studies using ¹²5I davalintide revealed no appreciable dissociation from the amylin nucleus accumbens receptor after 7 h while ¹²5I rat amylin did dissociate from this receptor (K(off) = 0.013/min). Sustained SC infusion of davalintide (275 µg/kg/day) or amylin (300) decreased plasma glucose after an oral glucose challenge at 2 weeks (by 27 and 31%) and suppressed gastric emptying at 3 weeks (by 29 and 47%), demonstrating durable glucoregulatory actions of both peptides. CONCLUSIONS: These data show glucoregulatory properties of davalintide consistent with amylin agonism and suggest that slowed receptor dissociation plays a role in davalintide's prolonged pharmacodynamic actions.


Subject(s)
Appetite Depressants/pharmacology , Blood Glucose/drug effects , Glucagon/drug effects , Islet Amyloid Polypeptide/pharmacology , Peptides/pharmacology , Satiety Response/drug effects , Animals , Body Weight , Dose-Response Relationship, Drug , Eating , Gastric Emptying/drug effects , Injections, Subcutaneous , Male , Rats , Rats, Sprague-Dawley
8.
Int J Obes (Lond) ; 34(2): 385-95, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19935749

ABSTRACT

OBJECTIVE: The current set of studies describe the in vivo metabolic actions of the novel amylin-mimetic peptide davalintide (AC2307) in rodents and compares these effects with those of the native peptide. RESEARCH DESIGN AND METHODS: The anti-obesity effects of davalintide were examined after intraperitoneal injection or sustained peripheral infusion through subcutaneously implanted osmotic pumps. The effect of davalintide on food intake after lesioning of the area postrema (AP) and neuronal activation as measured by c-Fos, were also investigated. RESULTS: Similar to amylin, davalintide bound with high affinity to amylin, calcitonin and calcitonin gene-related peptide receptors. Acutely, davalintide displayed greater suppression of dark-cycle feeding and an extended duration of action compared with amylin (23 versus 6 h). Davalintide had no effect on locomotor activity or kaolin consumption at doses that decreased food intake. Davalintide-induced weight loss through infusion was dose dependent, durable up to 8 weeks, fat-specific and lean-sparing, and was associated with a shift in food preference away from high-fat (palatable) chow. Metabolic rate was maintained during active weight loss. Both davalintide and amylin failed to suppress food intake after lesioning of the AP and activated similar brain nuclei, with davalintide displaying an extended duration of c-Fos expression compared with amylin (8 versus 2 h). CONCLUSION: Davalintide displayed enhanced in vivo metabolic activity over amylin while retaining the beneficial properties possessed by the native molecule. In vitro receptor binding, c-Fos expression and AP lesion studies suggest that the metabolic actions of davalintide and amylin occur through activation of similar neuronal pathways.


Subject(s)
Amyloid/pharmacology , Appetite Depressants/pharmacology , Body Weight/drug effects , Eating/drug effects , Peptides/pharmacology , Satiety Response/drug effects , Weight Gain/drug effects , Animals , Body Weight/physiology , Dose-Response Relationship, Drug , Eating/physiology , Energy Metabolism/drug effects , Energy Metabolism/physiology , Islet Amyloid Polypeptide , Male , Rats , Rats, Sprague-Dawley , Satiety Response/physiology , Weight Gain/physiology
9.
Int J Obes (Lond) ; 30(9): 1332-40, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16534527

ABSTRACT

BACKGROUND: Exenatide (exendin-4) is an incretin mimetic currently marketed as an antidiabetic agent for patients with type 2 diabetes. In preclinical models, a reduction in body weight has also been shown in low-fat-fed, leptin receptor-deficient rodents. OBJECTIVE: To more closely model the polygenic and environmental state of human obesity, we characterized the effect of exenatide on food intake and body weight in high-fat-fed, normal (those with an intact leptin signaling system) rodents. As glucagon-like peptide-1 receptor agonism has been found to elicit behaviors associated with visceral illness in rodents, we also examined the effect of peripheral exenatide on kaolin consumption and locomotor activity. METHODS AND RESULTS: High-fat-fed C57BL/6 mice and Sprague-Dawley rats were treated with exenatide (3, 10 and 30 microg/kg/day) for 4 weeks via subcutaneously implanted osmotic pumps. Food intake and body weight were assessed weekly. At 4 weeks, body composition and plasma metabolic profiles were measured. Kaolin consumption and locomotor activity were measured in fasted Sprague-Dawley rats following a single intraperitoneal injection of exenatide (0.1-10 microg/kg). Exenatide treatment in mice and rats dose-dependently decreased food intake and body weight; significant reductions in body weight gain were observed throughout treatment at 10 and 30 microg/kg/day (P<0.05). Decreased body weight gain was associated with a significant decrease in fat mass (P<0.05) with sparing of lean tissue. Plasma cholesterol, triglycerides and insulin were also significantly reduced (P<0.05). Exenatide at 10 microg/kg significantly reduced food intake (P<0.05) but failed to induce kaolin intake. In general, locomotor activity was reduced at doses of exenatide that decreased food intake, although a slightly higher dose was required to produce significant changes in activity. CONCLUSION: Systemic exenatide reduces body weight gain in normal, high-fat-fed rodents, a model that parallels human genetic variation and food consumption patterns, and may play a role in metabolic pathways mediating food intake.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/administration & dosage , Obesity/prevention & control , Peptides/administration & dosage , Venoms/administration & dosage , Animals , Body Composition , Body Weight/drug effects , Eating/drug effects , Exenatide , Female , Hypoglycemic Agents/adverse effects , Kaolin/administration & dosage , Male , Mice , Mice, Inbred C57BL , Motor Activity/drug effects , Peptides/adverse effects , Rats , Rats, Sprague-Dawley , Venoms/adverse effects
10.
Breast Cancer Res Treat ; 96(3): 279-92, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16328721

ABSTRACT

Several estrogen mimics (xenoestrogens) inappropriately activate the estrogen receptor (ER) in the absence of endogenous ligand. Given the importance of the ER in breast cancer growth and regulation, delineating the impact of these agents under conditions related to tumor treatment is of significant importance. We examined the effect of two prevalent xenoestrogens (bisphenol A and coumestrol) on ER activation and ER-dependent mitogenesis in breast cancer cells. We show that the ability of these agents to induce mitogenesis was restricted to conditions of estrogen depletion, and that these agents failed to cooperate with estradiol to induce MCF-7 breast cancer cell growth. These observations are consistent with the impact of each agent specifically on exogenous ER activation as monitored in HeLa cells, wherein the xenoestrogens activated the receptor in the absence of estradiol but failed to cooperate with estrogen. Tamoxifen blocked bisphenol A and coumestrol-mediated ER activation, indicating that exposure to these agents is unlikely to disrupt such therapeutic intervention. The response of tumor-derived ER alleles to these xenoestrogens was also examined. Although the xenoestrogens failed to alter ER-Y537S function, the ER-D351Y mutant demonstrated an enhanced response to bisphenol A. Moreover, tamoxifen enhanced the agonistic effects of xenoestrogens on ER-D351Y. Lastly, we examined the impact of ER co-activator overexpression on xenoestrogen response. Bisphenol A and coumestrol exhibited differential responses to co-activators with regard to ER activation. However, when using mitogenesis as an endpoint, these co-activators were insufficient to provide a significant growth advantage. Combined, these data demonstrate that bisphenol A and coumestrol can impact ER activity and ER-dependent proliferation in breast cancer cells, but the influence of these agents is restricted to conditions of estrogen depletion, selective mutation of the ER, and expression of specific co-activators.


Subject(s)
Breast Neoplasms/pathology , Coumestrol/pharmacology , Phenols/pharmacology , Receptors, Estrogen/physiology , Transcription, Genetic/drug effects , Benzhydryl Compounds , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Estradiol/pharmacology , Female , Humans , Selective Estrogen Receptor Modulators/therapeutic use , Tamoxifen/pharmacology
11.
Cancer Lett ; 241(1): 1-12, 2006 Sep 08.
Article in English | MEDLINE | ID: mdl-16298040

ABSTRACT

Prostate cancer is a major health concern and is treated based on its hormone dependence. Agents that alter hormone action can have substantial biological effects on prostate cancer development and progression. As such, there is significant interest in uncovering the potential effects of endocrine disrupting compound (EDC) exposure on prostate cancer. The present review is focused on agents that alter hormone action in the prostate and how they may impact cancer growth or treatment.


Subject(s)
Endocrine Disruptors/toxicity , Prostatic Neoplasms/chemically induced , Androgens/physiology , Diet , Endocrine Disruptors/administration & dosage , Humans , Male , Mutagens , Prostate/growth & development , Prostatic Neoplasms/physiopathology , Receptors, Androgen/physiology
12.
Disabil Rehabil ; 25(3): 113-9, 2003 Feb 04.
Article in English | MEDLINE | ID: mdl-12648000

ABSTRACT

PURPOSE: A common disorder encountered by healthcare specialists is carpal tunnel syndrome (CTS). CTS is a neuropathy disorder caused by compression on the median nerve. METHOD: Currently, there are several treatment methods for CTS such as: (1) non-steroidal anti-inflammatory drugs (NSAIDs); (2) injection of medications; (3) immobilization by splinting; (4) rehabilitation modalities (therapeutic ultrasound, ASTM AdvantEDGE, stretching and strengthening); and (5) surgery by carpal tunnel release. RESULTS: While NSAIDs, injections, and splinting have shown promise in relieving symptoms, long-term outcomes have been poor. CONCLUSION: This article provides a background in current treatment methods and an insight into the focal point of the future.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Carpal Tunnel Syndrome/diagnosis , Carpal Tunnel Syndrome/therapy , Decompression, Surgical/methods , Physical Therapy Modalities/methods , Adult , Combined Modality Therapy , Electromyography , Female , Humans , Male , Manipulation, Orthopedic/methods , Middle Aged , Neural Conduction , Prognosis , Recovery of Function , Risk Assessment , Severity of Illness Index , Splints , Treatment Outcome
13.
Clin J Sport Med ; 10(1): 22-8, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10695846

ABSTRACT

OBJECTIVE: To compare different types of rehabilitation for anterior knee pain. DESIGN: Prospective, randomized, blinded, and controlled study of 64 participants with anterior knee pain. SETTING: Outpatient rehabilitation clinic and testing laboratory. PARTICIPANTS: Participants were assigned in randomized fashion to three rehabilitation groups: traditional home rehabilitation (n = 20); physical therapy (n = 21); and home rehabilitation with a modified vastus medialis obliquis (VMO) specific straight leg raise (Muncie method; n = 23). INTERVENTIONS AND MAIN OUTCOME MEASURES: Clinical data was obtained at 0, 2, 6, and 12 weeks. Cybex testing was performed at 0, 6, and 12 weeks. RESULTS: Clinical outcome for the Muncie method indicated a statistically significant improvement in subjective pain and functional impairment ratings. Cybex testing in patients using the Muncie method demonstrated a statistically significant improvement in pain-free isometric contractions and maximum voluntary contraction. There were no significant differences between traditional home therapy and physical therapy. CONCLUSION: Findings suggest that the Muncie method results in improved clinical outcome at a lower cost than traditional home and physical therapy and possibly improved VMO/quadriceps muscle balance. Patients with anterior knee pain may benefit from applying the Muncie method in a home therapy program.


Subject(s)
Arthralgia/rehabilitation , Knee Joint/physiopathology , Adult , Analysis of Variance , Arthralgia/etiology , Arthralgia/physiopathology , Cost-Benefit Analysis , Exercise Therapy/economics , Exercise Therapy/methods , Female , Follow-Up Studies , Home Care Services/economics , Humans , Isometric Contraction/physiology , Male , Muscle Contraction/physiology , Muscle, Skeletal/physiopathology , Prospective Studies , Range of Motion, Articular/physiology , Single-Blind Method , Treatment Outcome
14.
Sports Med ; 28(5): 375-80, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10593647

ABSTRACT

Lateral epicondylitis is a common problem among physically active individuals. One of the most important roles of the clinician is to provide the most effective rehabilitation intervention for the injured athlete and the physically active individual. Over 40 different treatment methods for lateral epicondylitis have been reported in the literature. Initially, lateral epicondylitis can be treated with rest, ice, tennis brace and/or injections. Injections are one of the most popular methods utilised, with a high success rate. However, when the condition is chronic or not responding to initial treatment, physical therapy is initiated. Common rehabilitation modalities utilised are ultrasound, phonophoresis, electrical stimulation, manipulation, soft tissue mobilisation, neural tension, friction massage, augmented soft tissue mobilisation (ASTM) and stretching and strengthening exercise. ASTM is becoming a more popular modality due to the detection of changes in the soft tissue texture as the patient progresses through the rehabilitation process. Other new modalities include laser and acupuncture. As a last resort for chronic or resistant cases, lateral epicondylitis may undergo surgery. Scientific research has found that all these methods have been inconsistently effective in treating lateral epicondylitis. Therefore, further research efforts are needed to determine which method is more effective.


Subject(s)
Tennis Elbow/therapy , Exercise Therapy , Humans , Tennis Elbow/rehabilitation , Tennis Elbow/surgery , Treatment Outcome
16.
Health Care Women Int ; 19(5): 365-80, 1998.
Article in English | MEDLINE | ID: mdl-9849186

ABSTRACT

Who is fighting for the right to die? Past literature has been mixed as to the membership of this social movement. In the current study, 6,398 Hemlock Society members were surveyed in an effort to answer questions concerning who is participating in the right to die movement, whether these participants are rapidly approaching their own death or reacting to the death of a loved one, and whether the movement is invigorated by singular activists. The findings indicate that older, white, wealthy, highly educated, economically and politically active women are in the forefront of the right to die movement. These women report currently being mentally and physically healthy, yet already having taken the steps that will allow them to have an element of control over their death. Finally, right to die support seems to be part of a larger collective network concerning health care and political policy issues.


Subject(s)
Euthanasia, Active, Voluntary , Euthanasia , Health Knowledge, Attitudes, Practice , Lobbying , Right to Die , Societies , Women , Adult , Aged , Aged, 80 and over , Euthanasia/legislation & jurisprudence , Female , Health Policy/legislation & jurisprudence , Humans , Male , Middle Aged , Right to Die/legislation & jurisprudence , Surveys and Questionnaires , United States , Women/education , Women/psychology
17.
Am J Physiol ; 275(1): R29-32, 1998 07.
Article in English | MEDLINE | ID: mdl-9688956

ABSTRACT

The misty (m) coat color mutation is commonly maintained in linkage disequilibrium with the obesity mutation diabetes (Leprdb) to serve as a marker for Leprdb genotype. Comparisons among Leprdb genotypes are made under the untested assumption that m has no effects on traits under investigation. We tested this assumption in a population segregating m in the absence of db. Analysis of growth curves revealed that m/m mice are smaller than M/M mice by the 2nd wk of life and remain smaller through the 5th wk of life. Analysis of variance of three traits measured at 35 days of age revealed that m/m mice are 8% shorter than M/M mice, weigh 15% less, and have 21% less inguinal adipose mass. These results indicate that m affects growth traits. Therefore, when m and Leprdb segregate in the same cross, interpretation of their effects is confounded by linkage. More accurate estimates of Leprdb genotype effects can be made by removing m from populations segregating Leprdb and using a direct assay to measure Leprdb genotype.


Subject(s)
Diabetes Mellitus/genetics , Growth/genetics , Hair Color/genetics , Linkage Disequilibrium , Obesity , Aging , Analysis of Variance , Animals , Body Weight/genetics , Crosses, Genetic , Female , Genetic Markers , Genotype , Male , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Sex Characteristics
18.
Med Sci Sports Exerc ; 30(6): 801-4, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9624634

ABSTRACT

This clinical case report demonstrates the clinical effectiveness of a new form of soft tissue mobilization in the treatment of excessive connective tissue fibrosis (scar tissue) around an athlete's injured ankle. The scar tissue was causing the athlete to have pain with activity, pain on palpation of the ankle, decreased range of motion, and loss of function. Surgery and several months of conventional physical therapy failed to alleviate the athlete's symptoms. As a final resort, augmented soft tissue mobilization (ASTM) was administered. ASTM is an alternative nonsurgical treatment modality that is being researched at Performance Dynamics (Muncip, IN). ASTM is a process that uses ergonomically designed instruments that assist therapists in the rapid localization and effective treatment of areas exhibiting excessive soft tissue fibrosis. This is followed by a stretching and strengthening program. Upon the completion of 6 wk of ASTM therapy, the athlete had no pain and had regained full range of motion and function. This case report is an example of how a noninvasive augmented form of soft tissue mobilization (ASTM) demonstrated impressive clinical results in treating a condition caused by connective tissue fibrosis.


Subject(s)
Ankle Injuries/therapy , Massage/methods , Pain Management , Physical Therapy Modalities/methods , Adult , Ankle Injuries/complications , Ankle Injuries/pathology , Chronic Disease , Fibrosis , Humans , Male , Pain/etiology , Range of Motion, Articular , Soft Tissue Injuries/therapy , Wound Healing
19.
Am J Clin Nutr ; 67(3): 405-11, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9497183

ABSTRACT

Changes in substrate oxidation with isoenergetic high-carbohydrate (HC) and high-fat (HF) diets in male nonathletic subjects, aerobically trained athletes, and weight-trained athletes were examined in a crossover study. A whole-room respiration chamber was used to measure 24-h energy expenditure (EE) and substrate oxidation with control, HC, or HF diets for 7 d. The nonathletic group had higher 24-h EE (P < 0.05), exercise EE (P < 0.03), and resting metabolic rate (P < 0.04) than did the aerobically trained athletes when these measurements were corrected for lean body mass. Fat oxidation was significantly correlated with lean body mass and diet. However, athletic status had no effect on substrate oxidation. Carbohydrate oxidation across groups increased acutely by 23% after 24 h of the HC diet (P < 0.0001). Carbohydrate balance increased significantly over time with the HC diet (P < 0.002) and decreased acutely after return to the control diet (P < 0.0001). With the HF diet, carbohydrate balance increased and was significantly different from balance with the control diet by day 7 (P < 0.03). Fat balance decreased significantly with both the HF (P < 0.04) and HC (P = 0.0075) diets by day 7. Carbohydrate oxidation correlated with carbohydrate intake with both the control (r = 0.61, P < 0.01) and HC diets (r = 0.59, P < 0.02), but not the HF diet. Fat oxidation was not correlated with fat intake. In conclusion, substrate oxidation in a respiration chamber is significantly affected by diet, but not by prior athletic training.


Subject(s)
Dietary Fats/administration & dosage , Energy Metabolism , Sports , Basal Metabolism , Dietary Carbohydrates/metabolism , Dietary Fats/metabolism , Humans , Male , Respiration
20.
Cancer Res ; 55(22): 5184-6, 1995 Nov 15.
Article in English | MEDLINE | ID: mdl-7585570

ABSTRACT

A potent modifying locus of intestinal tumorigenesis in the mouse was recently identified as secretory phospholipase A2 (sPLA2). The human homologue of sPLA2 maps to chromosome 1p35, a region frequently lost in human tumors. To evaluate the possibility that sPLA2 was a tumor suppressor gene that was the target of the 1p loss events, we identified polymorphisms within the human sPLA2 gene. Using these polymorphisms, 31% of 16 colorectal carcinomas were found to lose a sPLA2 allele. However, sequence analysis of the complete coding region of sPLA2 revealed no somatic mutations in the remaining allele of those tumors with allelic loss, nor in 18 additional colorectal cancers. Thus, sPLA2 is within the chromosomal region often lost during colorectal tumorigenesis, but mutations of this gene do not appear to play a major role in colorectal cancer development, and sPLA2 is unlikely to be the 1p35 tumor suppressor.


Subject(s)
Chromosome Deletion , Colorectal Neoplasms/genetics , Phospholipases A/genetics , Animals , Base Sequence , Colorectal Neoplasms/enzymology , Genes, Tumor Suppressor , Humans , Mice , Molecular Sequence Data , Phospholipases A2
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