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Drosophila second chromosomes which had received a dose of 1000 R of X-rays were studied for heterozygous effects of newly-induced mutations on viability. In both homozygous and heterozygous backgrounds, the mean effect of radiation was not significantly different from zero. The results, therefore, do not support the experiments of Wallace and Mukai nor those reported by Maruyama and Crow.
Adult Japanese quail are sexually dimorphic. Even when implanted with testosterone (T), ovariectomized females fail to copulate and their cloacal glands are smaller than those of males. This may be due to a reduced capacity of the females to transform testosterone into active metabolites (estradiol-17 beta and 5 alpha-dihydrotestosterone). Indeed, in the male quail, estradiol-17 beta (E2) activates copulation whereas 5 alpha-dihydrotestosterone (5 alpha-DHT) activates crowing, strutting and the development of the cloacal gland. To test this hypothesis, we studied the effects of in vivo treatments of male and female quail with the different T-metabolites. Forty-one castrated male and female quail were implanted with subcutaneous silastic implants of T, 5 alpha-DHT, E2 and E2 in combination with 5 alpha-DHT. When implanted with these metabolites, females failed to copulate and their cloacal glands remained less developed than those of males. Sexual differences in behavior and morphology thus cannot be entirely explained by sexual dimorphism of the metabolism.
The applications of sterically crowed trialkyksilyl ether derivatives to the analysis and characterization by thin-layer chromatography, gas chromatography and mass spectrometry, of metabolites of 2alpha, 3alpha-cyclopropano-5alpha-androstan-17beta-ol in the rabbit are described. These derivatives are complementary to the familiar trimethysilyl ether derivatives, but have greater hydrolytic stability (an advantage for TLC), generally give better GC separations, and have characteristic mass spectra. Isomer differentiation by GC and MS is also more readily achieved than via the TMSi ether derivatives. These properties should make SCTASi ethers useful derivatives for studies of steroid metabolism.
The data reviewed here are compatible with the hypothesis that telencephalic dopamine activity is elicited by motivationally significant stimuli which in turn creates a neural state in which animals are more prepared to respond to significant stimuli in the environment. This analysis may be viewed as extensions of both the sensorimotor hypothesis, which depicts dopamine as potentiating the ability of stimuli to elicit responses (Clody and Carlton, 1980; Marshall et al., 1974; White, 1986) and of the incentive motivational hypothesis, which emphasizes the importance of dopamine in responding to stimuli that serve as signals of biologically significant events (Blackburn et al., 1989a; Crow, 1973; Mogenson and Phillips, 1976). In addition, we have sought to emphasize that not all responses are equally dependent upon the integrity of forebrain dopamine activity. Some responses, such as ingestion of standard foods by hungry animals, copulation, and escape, are relatively impervious to dopamine disruption. Further, once other behaviours, such as avoidance or appetitive operant responses, have been acquired, they can be maintained at an initially high rate despite perturbation of dopamine systems, although performance deteriorates with repeated testing. This analysis has emerged from the joint consideration of how both appetitive and defensive behaviours are influenced by dopamine antagonists, along with an examination of dopamine release during sequences of behaviour. The data reviewed suggest that dopamine is involved in fundamental psychological processes through which environmental stimuli come to exert control over certain aspects of behaviour. In the future, as knowledge in this field advances, there will have to be an integration of the literature on dopamine and motivation with the literature on dopamine and motor systems. We expect that dopamine release will be seen as a mechanism by which important environmental cues, of innate or learned significance, lead to a general enhancement of motor skeletal responses directed towards distal cues. We conclude with a caveat: Caution must be exercised when attempting to infer a general role of any neurotransmitter in motivated behaviour based on the study of a limited number of motivational systems. Although neurotransmitter pathways may figure prominently in the control of certain behaviours, it is incorrect to think of neurotransmitters as having a single role in behaviour. However, when comparative analyses reveal a common thread among different motivational systems, as is becoming apparent for the general role of mesotelencephalic dopamine pathways in behaviour, then the goal of generating coherent and comprehensive theory concerning a neurotransmitter's function in behaviour will begin to be realised.(ABSTRACT TRUNCATED AT 400 WORDS)
A characteristic 'crow's foot' pattern is seen around the eye in many flash burns. The protective blink reflex underlies this, and the injury is due to convected rather than radiant energy.
We studied the non-specific responses of GH and PRL to gonadotropin releasing hormone (GnRH) in eleven male patients aged 18-30 in whom a diagnosis of acute schizophrenia was made according to Crow's criteria. GnRH administration was followed by a significant increase in plasma GH in five patients; plasma PRL increased in two patients. The two prolactin responders were also GH responders. Non-specific GH response was confirmed on repeated testing in two patients in whom GnRH stimulation was performed twice. During saline control, non-specific hormone responses were not observed. The abnormal hormone responses observed in acute schizophrenia are probably due to the disordered monoamine regulation characteristic of this condition.
PURPOSE: The purpose of this study was to examine whether 3-amino-benzamide (3ABA), an inhibitor of poly (ADP-ribose) synthesis, inhibits the two types of potentially lethal damage (PLD) repair, termed slow and fast. METHODS AND MATERIALS: The fast-type PLD repair was measured by the decrease in survival of V79 Chinese hamster cells by postirradiation treatment with 3ABA. The slow-type PLD repair was measured by the increase in survival by posttreatment with conditioned medium (CM), which became conditioned by growing a crowed culture of cells and supports the slow-type PLD repair. RESULTS: Up to 1 mM, 3-ABA inhibited the slow type repair; at doses of 2 mM and above, it inhibited the fast type of PLD repair. CONCLUSION: There are quantitative differences in cellular effects of 3ABA dependent on concentration. Poly (ADP-ribose) appears to play an important role in the PLD repairs and has little effect on the repair of sublethal damages.
Replicas of the apical surface of hair cells of the inner ear (vestibular organ) were examined after quick-freeze, deep-etch and rotary shadowing. With this technique we demonstrate how actin filaments are organized and associated with the plasma membrane in the stereocilia and cuticular plate as well as inside the junctional complex. In each stereocilium there are thread-like connectors running from the actin filament bundle to the limiting membrane. Many of the actin filaments in the cuticular plate are connected to the apical cell membrane by tiny branched connecting units like a 'crow's foot'. Where these 'feet' contact the membrane there is a small swelling. These branched 'feet' extend mainly from the ends of the actin filaments but some connect the lateral surfaces of the actin filaments as well. Actin filaments in the cuticular plate are also connected to each other by finer filaments, 3 nm in thickness and 74 +/- 14 nm in length. These 3 nm filaments (which measure 4 nm in replicas) connect actin filaments, not only of the same polarity, but of opposite polarities as documented by examining replicas of the cuticular plate which had been decorated with subfragment 1 (S1) of myosin. At the apicolateral margins of the cell we find two populations of actin filaments, one just beneath the tight junction as a network, the other at the level of the intermediate junction as a ring. The latter is composed of actin filaments that run parallel to each other; adjacent filaments often show opposite polarities, as evidenced by S1 decoration. Because of the polarity of the filaments this ring may be a 'contractile' ring.
The authors present a consecutive series of 38 arthroplasties for osteoarthrosis secondary to hip dysplasia. All arthroplasties were performed by a single surgeon using Mittelmeier II (Autophor, Osteo AG, Selzach, Switzerland) ceramic cementless components. Crowe grades of subluxation were 60% grade I, 16% grade II, 12% grade III, and 12% grade IV. In all cases, the acetabular component was seated in the true acetabulum. The mean follow-up period was 75 months (range, 40-122 months). By the time of review, six hips (16%) had required revision for aseptic loosening, mainly of the femoral component. Good or excellent results were achieved in only 63% of the patients. In the group of surviving arthroplasties, the median Charnley hip scores before surgery were: pain, 2; movement, 3; and walking, 3. After surgery, the scores were: pain, 5; movement, 5; and walking, 6. All improvements were significant. The mean postoperative Harris hip score was 84. Poor scores were associated with contralateral hip disease (2 cases) and spina bifida (2 cases), significantly affecting function. The Autophor prosthesis can produce satisfactory results in some of these young patients with hip dysplasia. However, femoral loosening is a major problem and because of this, the authors have since changed to a newer stem design.
Addressing health inequity is now recognized as a clinical competency in medical education. We examined the career and writings of Robert Wilson Jr. (1867-1946), longtime dean of the Medical College of the State of South Carolina during the Jim Crow Era, using primary and secondary sources within the context of systemic and structural racism, particularly in South Carolina. Wilson used public health data to refute the "Black Extinction Hypothesis" rooted in social Darwinism. He challenged assumptions of inherent Black susceptibility to tuberculosis, linking disease instead to social determinants of health. He also identified disproportionate mortality from kidney and cardiovascular disease among Black populations, anticipating modern health disparities research. Wilson further acknowledged systemic injustice and implicated structural conditions, including housing, in shaping outcomes. In an era of continuing health inequity and racial health disparities, Wilson applied empirical evidence to reject biological determinism, identify outcomes disparities, and advocate for racial justice.
As usual, the face at rest is analysed before btx injection. But the interest of the analysis of the face dynamically, in a functional way, with the help of the palpation, is demonstrated. A key point is to decide to favor the high position of the highbrow more than to totally fade the frontal wrinkles. To perform this, a new functional segmentation of the frontalis muscle is described. The role of the procerus muscle as antagonist of the frontalis muscle, inferior medial part, is explained. To elevate the medium third of the eyebrow, the lateral part of the corrugator muscle is injected with a specific technique. This technique decreases the risk of weakening the overlying frontalis muscle and the underlying levator palpebrae muscle. To achieve a higher elevation of the eyebrow tail, and to totally fade the upper and medium crow's foot, different points of injection on the lateral orbital rim are described, without the risk of migration to the oculo motor muscles. Fading the tear trough with the injection of the superior malar part of the orbicularis oculi muscle is explained. Thanks to the use of the functional analysis of the face and to the comprehension of the fabulous possibilities of the botulinum toxin A, it is now justified to switch from a "ready to wear" way of injection to a "haute couture" way, that is to say adapted to each patient.
A hamster model infected with a New York crow brain isolate of West Nile virus (WNV) was characterized for evaluating potential antiviral therapies. Older hamsters (7-11 weeks old) had a lower mortality of approximately 50% and more apparent disease signs as compared to >90% mortality in younger hamsters and mice. Disease signs such as limb strength, lacrimation, front limb tremors, somnolence, and deficiencies in neurological responses were noted at different times after viral injection. Weight loss was a marker for WNV disease signs, whereas, the ability to climb up an inclined ramp was associated with whether the animals survived the disease or died. Infectious WNV assays performed on tissues from hamsters during development of the infection indicated that viral titers peaked first in plasma, but that titers were eventually highest in kidney tissue. Viral titers achieved maximal levels in brain tissue on 6 dpi, which was 1-2 days before strong neurological signs and death started to occur. Maximal spleen and plasma titers were achieved sooner in young hamsters as compared with older hamsters, which correlated with increased susceptibility. To test the hypothesis that older hamsters would be more sensitive for identifying antiviral effects, Infergen, a consensus human interferon-alpha highly active against WNV in cell culture, was administered subcutaneously to older and younger hamsters beginning on 2 dpi. The effects of Infergen on weight change, survival, and climbing ability of infected animals were more apparent in older hamsters than in younger hamsters. The use of older hamsters is another WNV-infectious model, in addition to mice, for evaluating potential antiviral therapies.
The outcome of 33 total hip arthroplasties using an acetabular reinforcement ring with hook for osteoarthritis associated with developmental dysplasia of the hip was reevaluated after a minimal follow-up of 10 years (average, 10.8 years). Most cases comprised Crowe type II (22 hips) and type III (7 hips) dysplasia. The mean D'Aubigné score increased from 7 to 15 points. Three revisions (9%) were performed for aseptic loosening, 2 of them had a structural autograft. None of the unrevised 30 acetabular reconstructions showed definite radiographic signs of loosening. These results compare favorably with the literature and the acetabular reinforcement ring with hook presents a versatile tool for acetabular bone stock deficiencies.
Measurement of social status is an important component of many behavioural studies. A variety of techniques have been developed and adopted, but while there have been some analyses of index properties using simulated data, the rationale for selecting a method remains poorly documented. As a first step in exploring the implications of index choice, we compared the characteristics of eight popular indices by applying each to the same data set from interactions between male fowl Gallus gallus, the system in which social hierarchies were first described. Data from eight social groups, observed over four successive breeding seasons, were analysed to determine whether different indices produced consistent dominance scores. These scores were then used in tests of the relation between social status and crowing to explore whether index choice affected the results obtained. We also examined the pattern of dominance index use over the last decade to infer whether this has likely been influenced by tradition, or by taxa of study animal. Overall agreement among methods was good when groups of birds had perfectly linear hierarchies, but results diverged when social structure was more complex, with either intransitive triads or reversals. While all regression analyses revealed a positive relationship between dominance and vocal behaviour, there were substantial differences in the amount of variance accounted for, even though the original data were identical in every case. Index selection can hence perturb estimates of the importance of dominance, relative to other factors. We also found that several methods have been adopted only by particular research teams, while the use of others has been taxonomically constrained, patterns implying that indices have not always been chosen solely upon their merits. Taken together, our results read as a cautionary tale. We suggest that selection of a dominance index requires careful consideration both of algorithm properties and of the factors affecting social status in the system of interest.
A new serotype of botulinum toxin has recently arrived in the US. Botulinum toxin type B (BTX-B), known as Myobloc in the United States and as Neurobloc in Europe, is one of seven different antigenic members of the botulinum toxin family, five of which the human nervous system is susceptible to. Like botulinum toxin type A (BTX-A), BTX-B has been used for a myriad of both dermatologic and nondermatologic problems since its recent approval by the FDA for the treatment of cervical dystonia in December 2000. It is currently not approved however, for a cosmetic use but has been used for this purpose in an "off-label" fashion. It has followed in the therapeutic footsteps of BTX-A in the prevention and treatment of facial wrinkles such as crow's feet and glabellar frown lines. In addition, one of its current and popular uses is in the management of hyperhidrosis, a disease in search of a long needed treatment. This past year researchers have been investigating the efficacy as well as defining the dosing and application regiments of BTX-B in the treatment of hyperhidrosis. In addition, recent studies have been examining its side effect profile, which may be very different than that seen with BTX-A. There are only a handful of studies in the literature examining the cosmetic applications of BTX-B. This chapter will review what is currently known about BTX-B and its current use in regards to the treatment of hyperhidrosis.
One of the most common etiologic forces for the persistence of facial rhytides is the repetitive contraction of the intrinsic muscles that are necessary for facial expression. These include the forehead lines, crow's feet, glabellar rhytides, and wrinkles in the lower face. Although filling agents such as collagen and laser procedures can help reduce the appearance of these lines, they do not address the underlying forces that cause these wrinkles to persist. Botulinum toxin type-A and type-B are neurotoxins that address these issues and result in the relaxation of the intrinsic facial muscles and subsequent resolution of these dynamic facial rhytides. This article will compare the efficacy, duration, dose ranging studies, and safety in the treatment of facial rhytides with both types of toxins. In addition, the treatment of hyperhidrosis with type-A and type-B botulinum toxin will also be discussed.
The use of botulinum toxin (BTX) in the lower one third of the face has rapidly become one of the most popular ways to rejuvenate the face, due to the effectiveness of BTX in this area and the lack of major side effects. It is recommended that physicians planning on treating patients in this area of the face first have extensive experience treating the more traditional areas, such as the forehead, glabella, or crow's feet, because the inferior one third of the face has many co-dependent and interdigitating (interrelated) muscles that are very sensitive and readily affected by minimal amounts of BTX. We prefer to reconstitute a 100-U vial of Botox(R) with 1-2.5 mL of saline solution because some of the muscles in this area of the face are very sensitive to diffusion of the toxin and will be weakened beyond the area originally planned for treatment.
Cosmetic use of BTX has skyrocketed in recent years, especially since the approval of BTX-A for treatment of glabellar lines. Complications and adverse reactions can easily arise, particularly for the novice injector. This paper provides insights from an experienced physician on how to avoid these complications, and how to treat them when and if they occur. The main cosmetic uses for BTX are analyzed for possible complications and adverse events. Injection techniques are discussed. Comparisons between BTX-A and BTX-B are given to point out the need for different injection techniques based on the product being used. Treatment recommendations for the Glabella, Brow, Crow's Feet, Upper Lip Wrinkling/Lines, Depressor Anguli Oris, Nasolabial Folds, Mentalis, Neck and Hyperhidrosis are discussed, as well as systemic complications. It is important for the injecting physician to be familiar with these potential complications, even though the use of BTX has been safe and generally well tolerated, because it will lead to even greater success with the use of BTX.