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PubMed1975

The genetic structure of a tribal population, the Yanomama Indians. XII. Biodemographic studies.

The Yyanomama Indians of Southern Venezuela and Northern Brazil are one of the largest, relatively unacculturated tribes of the tropical rain forest. Over a period of eight years data have been collected from a considerable portion of their territory on estimated age, sex ratio, fertility rates (as determined by physical examination and urine tests), and infant death rates. Although it has been impossible to collect direct data on infanticide, this subject can be approached indirectly through distortions of the sex ratio and anecdotal information. Some historical data are also available as a basis for estimating tribal expansion in the past 100 years. With this material it has been possible to construct Life Tables for the anomama,, and to explore the results of various perturbations of the input parameters. Data are also presented on patterns of mating and reproduction: number of spouses, mean and variance in number of surviving children, frequency of "extra-marital conceptions" based on the results of extensive blood group typings, and consanguinity rates as determined by observation and computer simulation. Although we do not present the Yanomama as typical, these data are seen as providing a basis for more realistic population models than have existed in the past. In addition, the data provide a basis for relatively precise estimates of such demographic measures as Fisher's Reproductive Value, Crow's Index of Total Selection, and Weiss' Index of Growth Regulation.

Adolescent↗
PubMed1975

Demography and evolution of an urban ethnic community: Polish Hill, Pittsburgh.

Polish Hill is an urban, ethnic enclave of approximately 3000 residents residing in a 25-block area of Pittsburgh. This paper documents changes in the fertility, morbidity, and mortality patterns in the community from the turn of the century to the present. The demographic reconstruction is based upon baptismal and marriage records, the administration of demographic proformae and population censuses. The high mortality, morbidity, and fertility variance suggest that the immigrant population has experienced a period of high opportunity for selection in the early 1900's and that Crow's index was gradually reduced to its present level.

Adolescent↗
PubMed2006

Urban and rural differences in mortality and causes of death in historical Poland.

The purpose of this paper is to document and interpret urban-rural differences in mortality in the past. To this end, we used data on mortality in Wielkopolska, Poland, in the 19th century and at the beginning of the 20th century. The data on mortality in rural areas (N = 1,173,910 deceased), small towns (N = 573,903 deceased), and Poznań, the capital of the Wielkopolska region (N = 86,352 deceased), were gathered from original Prussian statistical yearbooks (Preussische Statistik). Causes of death were also analyzed (rural areas, N = 449,576 deceased; small towns, N = 238,365 deceased; Poznań, N = 61,512 deceased). Mortality measures such as crude death rate (CDR), infant death rate (IDR), and neonatal and postneonatal death rates were calculated. Life tables were constructed for both stationary and stable population models and measures of the opportunity for natural selection calculated (Crow's index I(m), potential gross reproduction rate R(pot), and biological state index I(bs)). Relative frequencies of leading causes of death were computed. Stratification depending on the place of residence was evident in all mortality measures as well as in the values of the life tables and the measures of the opportunity for natural selection, but it was reverse of what is observed today in developed countries. In Poznań (a large industrial city), the mortality situation was the least favorable. It was caused by large population density, lack of water supply and sewage systems (up to 1896), and bad working conditions. The values of CDR ranged between 26.89-31.46, and IDR between 190.6-280.5. Newborn life expectancy (for a stable population model) was 31.6 years, I(m) = 0.79, R(pot) = 0.85, and I(bs) = 0.47. The most common causes of death were tuberculosis, other diseases of the respiratory and circulatory systems, dysentery and diarrhea, and cancer. These diseases were less common in rural areas, so they had the most favorable values of mortality measures (CDR between 22.87-27.32, IDR between 181.8-219.4, life expectancy of newborn e(0) = 42.12, I(m) = 0.55, R(pot) = 0.93, I(bs) = 0.60). Infectious diseases (other than tuberculosis), frailty at birth, and frailty in old age were the most frequent causes of death in rural areas. Small towns (population <20,000) had a mortality intermediate between city and rural areas.

Cause of Death↗
PubMed1977

Recurrent ulcer after proximal gastric vagotomy for duodenal and pre-pyloric ulcer.

Factors thought to be important in the development of recurrent ulcer after proximal gastric vagotomy were investigated 1-4 years after operation in 211 patients with duodenal ulcer and in 49 with pre-pyloric ulcer. Recurrent ulcer was found in 25 patients with duodenal ulcer (12 per cent) and in 6 with pre-pyloric ulcer (12 per cent). Recurrence was not related to age, sex, duration of dyspepsia, radiological findings or peak acid output before and 10 days after vagotomy. Fifty-six patients were operated upon by the method of Amdrup and Jensen (1970), including skeletonization of about 2 cm of the oesophagus. The remaining 204 patients were operated on by a technique in which the dissection of the lesser curve was begun at the 'crow's foot' and the oesophageal dissection was extended, in most cases, to more than 4 cm above the cardia. Recurrence was more frequent among the 56 patients in the first group than among the remaining patients with duodenal ulcer. Recurrence was positively related to basal acid output after vagotomy. An increase of peak acid output of 50 per cent was seen in a smaller group with recurrence and patients with dyspepsia within 18 months of vagotomy. It was concluded that the risk of recurrence is not related to the number of parietal cells, as expressed by peak acid output to histamine. The risk may probably be reduced by extension of the oesophageal skeletonization. A marked increase in peak acid output may be seen during the first year after proximal gastric vagotomy in patients with recurrence or dyspepsia.

Duodenal Ulcer↗
PubMed1981

A comparison of the Burge and Grassi intraoperative tests for completeness of nerve section in parietal cell vagotomy.

The Burge and Grassi tests were compared in 22 patients after parietal cell vagotomy. Dissection was continued until the Burge test was negative or until no further nerve fibres could be found. Three Burge-negative patients were Grassi-positive, 2 due to inadequate division of the terminal branches of the nerve of Latarjet at the 'crow's foot' and 1 due to epiploic fibres. One Burge-positive patient was also Grassi-positive but the latter test indicated the position of an undivided oesophageal nerve fibre. It is concluded that the Grassi intraoperative test for completeness of vagotomy is superior to the Burge procedure because it shows how much stomach needs to be vagotomized to denervate the parietal cells and abolish gastric acid secretion and also indicates the position of residual fibres if vagotomy is incomplete.

Adult↗
PubMed1977

Mechanics of the syrinx in Gallus gallus. II. Electromyographic studies of ad libitum vocalizations.

Records of electrical activity in the tracheal muscles of domestic chickens were obtained for a variety of ad libitum vocalizations. Primary attention was given to an analysis of events during the most complex call, crowing. Three pairs of muscles, Mm, tracheohyoideus, tracheolateralis, and sternotrachealis, can affect the configuration of a chicken's syrinx. The firing patterns of the three muscle pairs are related to their different abilities to affect the tension of the syringeal membranes. The influence of M. tracheohyoideus is most indirect and imprecise, and its role the least clearly defined. It appears to adjust the position of the trachea so that the syrinx is isolated from unpredictable and/or undesireable consequences of nuchal position and tracheal elasticity, and also helps draw the glottis caudad, thereby deepening the pharyngeal chamber. The other two muscles interact to control the tension of the vocal membranes. M. sternotrachealis relaxes the membranes by drawing the drum of the trachea caudad, or, via the syringeal ligament, by rotating the pessulus cranioventrad, or both. M. tracheolateralis tenses the membranes and/or prevents caudal movement of the orgin of M. sternotrachedalis, a necessity if the syringeal ligament is to rotate the pessulus. Vocalization depends on both syringeal configuration and appropriated air flow. Hence, tracheal muscles, syrinx, air sacs, and ventilatory muscles cooperate to form a vocal system. Cooperation elicits a surprising degree of redundancy. At least one call, a high pitched wail, may be produced by two very different techniques.

Animals↗
PubMed2002

History and current practice of tonsillectomy.

OBJECTIVE: To review important developments in the history of adenotonsillectomy and describe current methods and results for the operation. STUDY DESIGN: Review. METHODS: Tonsillectomy practices since antiquity were reviewed, with emphasis on introductions of new surgical tools and procedures, anesthesia methods, and patient care practices. Past and current indications for and complications associated with tonsillectomy were also reviewed. RESULTS: Devices used for adenotonsillectomy have included snares, forceps, guillotines, various kinds of scalpels, lasers, ultrasonic scalpels, powered microdebriders, and bipolar scissors. General anesthesia, the Crowe-Davis mouth gag, and methods for controlling bleeding have contributed greatly to success with the operation. Past and current indications for adenotonsillectomy are similar, although the relative importance of some indications has changed. The complication rate has declined, but the problems that do occur remain the same. Currently, cost-effectiveness is a principal concern. CONCLUSION: The instruments and procedures used for adenotonsillectomy have evolved to render it a precise operation. Today, the procedure is a safe, effective method for treating breathing obstruction, throat infections, and recurrent childhood ear disease.

Adenoidectomy↗
PubMed1998

The familial amyotrophic lateral sclerosis-associated amino acid substitutions E100G, G93A, and G93R do not influence the rate of inactivation of copper- and zinc-containing superoxide dismutase by H2O2.

Inactivation of copper- and zinc-containing superoxide dismutase (Cu,ZnSOD) by H2O2 is the consequence of several sequential reactions: reduction of the active site Cu(II) to Cu(I) by H2O2; oxidation of the Cu(I) by a second H2O2, thus generating a powerful oxidant, which may be Cu(I)O or Cu(II)OH or Cu(III); and finally oxidation of one of the histidines in the ligand field, causing loss of SOD activity. Three familial amyotrophic lateral sclerosis (FALS)-associated mutant Cu,ZnSODs, i.e., E100G, G93A, and G93R, did not differ from the control enzyme in susceptibility to inactivation by H2O2. It thus appears that an increased peroxidase activity of the FALS-associated Cu,ZnSOD variants might not be a factor in the development of this disease. This leaves the loss of Zn, and the consequent increase in peroxidase activity, or in nitration activity, as a viable explanation (J. P. Crow et al., 1997, J. Neurochem. 69, 1936-1944), among other possibilities.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Woodpigeons nesting in association with hobby falcons: advantages and choice rules.

Many bird species nest in close association with other bolder and more aggressive birds which provide protection against nest predators. The woodpigeons, Columba palumbus, that nest in poplar plantations in Northern Italy are found almost exclusively clumped around hobby, Falco subbuteo, nests. Woodpigeons settle in the area and build their nests after the hobby has started nesting. We carried out experiments with dummy nests and observations on woodpigeon nests. Dummy woodpigeon nests placed near a hobby's nest suffered less depredation by hooded crows, Corvus corone cornix, than those placed far from it. A logistic regression analysis showed that three variables, hobby nesting stage, distance from the hobby's nest and the hobby's aggressiveness, influenced the probability of nest predation. The degree of protection varied during the hobby's nesting period and was highest when chicks were in the nest. The hobby's aggressiveness against intruders varied both between and within individuals during different nesting phases. The predation rate of dummy nests associated with the falcon was negatively correlated with the aggressiveness score of the hobby during the 6 days of dummy nest exposure. Observations on real nests showed that woodpigeons selected hobbies that had a high fledging success, and a more vigorous defensive behaviour. Clues that would allow woodpigeons to choose the best protector may be early nesting by the hobby and its aggressiveness. Hobbies preyed on adult woodpigeons, but the risk incurred by the woodpigeons was low compared with the very high risk of nest predation in this area. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1996

Sex steroid-opioid interactions associated with the temporal component of avian calling patterns.

Isolation from conspecifics in young, precocial birds predictably induces distress vocalizations (DV) and androgens change this type of vocalization into male typical "crowing" (CR). In addition, opioid peptides are known to exert potent effects on avian vocal behavior. Here we investigate the organizational and activational correlates of sex-steroid actions on opioid-receptor organization and their relevance to the temporal evolution of DV and CR. From the effects of pre- and postnatal steroid applications and postnatal [3H]etorphin binding studies, we find that early steroidal effects become manifested at the behavioral level by changing the characteristic duration of vocalizations. In the male quail this extension of calling duration is accompanied by a clear decrease in opiate binding, whereas in the female there is a moderate increase in binding sites. The transition from DV to CR (within hours) induced by testosterone is correlated with "upregulation" of opiate receptor sites within unilateral brainstem areas of young male quail. Based on these findings, we suggest that organizational steroid effects change the characteristic duration of isolation-induced vocalizations and these effects appear to be manifested at the level of opioid-receptor distribution.

Animals↗
PubMed1996

Phylogenetic relationships among the major lineages of the birds-of-paradise (Paradisaeidae) using mitochondrial DNA gene sequences.

Complete mitochondrial cytochrome b gene sequences were determined from 12 species of the Australo-Papuan birds-of-paradise (Paradisaeidae) representing 9 genera. Phylogenetic analysis of these and 5 previously published sequences reveals a radiation of the main paradisaeinine lineages that took place over a relatively short evolutionary time scale. The core paradisaeinines are resolved as the monophyletic sister-group to the crow-like manucodines. The genus Parotia is basal to other paradisaeinines and is not closely related to the morphologically similar genera Ptiloris and Lophorina. Three major clades within the paradisaeinine ingroup include: (1) Cicinnurus and Diphyllodes, (2) Ptiloris and Lophorina, and (3) the genus Paradisaea. The monotypic genus Seleucidis is apparently closely related to clades (1) and (2). Cytochrome b sequences did not provide evidence for the monophyly of the sicklebill genera Epimachus and Drepanornis. The paradisaeid tree is characterized by short internodal distances. Thus, some clades cannot be strongly resolved by cytochrome b sequences alone.

Animals↗
PubMed1997

Effects of training procedure on memory formation using a weak passive avoidance learning paradigm.

One-day-old chicks will learn, in one trial, to avoid pecking a bead that tastes aversive. This procedure is used widely as a model for learning and memory, although a variety of training procedures and bead types are used in different laboratories. Here we report that the decay of memory following training on a weak (10% methylanthranilate) avoidance task is dependent on the training procedure rather than the characteristics of the beads or the strain of chick used. Chicks that have been presented with a bead in pretraining and a similar bead coated in MeA during training fail to avoid the bead when tested 2 h posttraining, whereas chicks presented with a bead of particular color and size for the first time at training demonstrate high levels of avoidance at 2 h posttraining. These results resolve the differences in the time course of memory formation for a weak passive avoidance task described by the groups at Monash University (Crowe, Ng, & Gibbs, 1989) and the Open University (Sandi & Rose, 1994).

Animals↗
PubMed2002

West Nile virus in livestock and wildlife.

WN virus is one of the most ubiquitous arboviruses occurring over a broad geographical range and in a wide diversity of vertebrate host and vector species. The virus appears to be maintained in endemic foci on the African continent and is transported annually to temperate climates to the north in Europe and to the south in South Africa. Reports of clinical disease due to natural WN virus infection in wild or domestic animals were much less common than reports of infection (virus isolation or antibody detection). Until recently, records of morbidity and mortality in wild birds were confined to a small number of cases and infections causing encephalitis, sometimes fatal, in horses were reported infrequently. In the period 1996-2001, there was an increase in outbreaks of illness due to WN virus in animals as well as humans. Within the traditional range of WN virus, encephalitis was reported in horses in Italy in 1998 and in France in 2000. The first report of disease and deaths caused by WN virus infection in domestic birds was reported in Israel in 1997-1999, involving hundreds of young geese. In 1999 WN virus reached North America and caused an outbreak of encephalitis in humans in the New York area at the same time as a number of cases of equine encephalitis and deaths in American crows and a variety of other bird species, both North American natives and exotics. Multi-state surveillance for WN virus has been in place since April 2000 and has resulted in the detection of WN virus in thousands of dead birds from an increasing number of species in North America, and also in several species of mammals. The surveillance system that has developed in North America because of the utility of testing dead birds for the rapid detection of WN virus presence has been a unique integration of public health and wildlife health agencies. It has been suggested that the recent upsurge in clinical WN virus infection in wild and domestic animals as well as in humans may be related to the emergence of one or more new strains of WN virus. Virus isolated in New York in 1999 was found to be identical to that from Israel. It was alarming for WN virus to so easily invade the United States and surprising that it became established so quickly in the temperature climate of New York. Its persistence and rapid expansion in the United States leave a number of unanswered questions. New disease characteristics and patterns have occurred and more are evolving as WN virus further invades the western hemisphere. Additional animal research is needed to answer these questions. Some of the research needs include bird migration as a mechanism of virus dispersal, vector and vertebrate host relationships, virus persistence mechanisms, laboratory diagnosis, viral pathogenesis, risk factor studies, vaccine development, and WN virus impact on wildlife (CDC 2001a). Determination of the primary reservoir host species that are involved in the epidemiology of WN virus and the suitable sentinel species for active surveillance are also important research areas.

Amphibians↗
PubMed1988

Experiences in psycho-surgery in The Netherlands.

The authors report on their experiences in 54 cases operated upon for various psychiatric diseases including compulsive neurosis, depression, anxiety, tension and in some of this group also automutilation; intractable temporal lobe epilepsy and aggressive behaviour; aggressive behaviour and minor epileptic problems; severe mental retardation, restlessness, automultilation and in some of this group also aggression. Operative procedures have been fronto-basal lesions according to Knight and Bridges, as well as lesions in the cingulum, the paracingular white matter, the anterior part of the radiation of the corpus callosum and the basal frontal region, using the technique of Crow. Amygdalotomy and thalamotomy was performed for epilepsy, aggression and automutilation in the mentally retarded patients. Because of the small number of patients and the variety of different diseases and techniques no statistically valid analysis of the results is possible.

Epilepsy↗
PubMedDate not supplied

Subperiosteal minimally invasive laser endoscopic rhytidectomy: the SMILE facelift.

Current concepts of total facial rejuvenation involve a comprehensive integrated approach to achieve a balanced youthful appearance. Recently introduced endoscopic-assisted techniques allow us to rejuvenate the face through small, remote incisions. Previously, we have considered only young patients with good skin turgor as candidates for minimally invasive procedures, but the advent of the resurfacing laser has allowed us to expand our indications for single stage minimal access rejuvenation. Full facial immediate laser resurfacing at the time of standard rhytidectomy has been avoided due to risk of flap necrosis. Subperiosteal minimally invasive endoscopic assisted techniques do not substantially interfere with facial blood supply. We can now perform endoscopic-assisted full facelifts combined with immediate laser resurfacing to reposition the tissues in a more youthful position and then tighten the skin envelope. Extended endoscopic-assisted subperiosteal forehead lift is performed through three to five scalp incisions; subperiosteal midface lift is performed through a crow's foot or intraoral incision. Cervicoplasty, if needed, is performed through a small submental incision. Full face laser resurfacing is done using a Coherent Ultrapulse laser. To date we have performed eleven subperiosteal minimally invasive laser endoscopic (SMILE) rhytidectomies. There has been no evidence of flap necrosis with this technique. Postoperative recovery has been no different from patients treated only by full face resurfacing, except perhaps for the slight increase in early facial edema. We believe the SMILE facelift is a viable alternative to standard techniques. The limitations of this procedure still need to be elucidated.

Adult↗
PubMedDate not supplied

Mimetic modulation for problem creases of the face.

Problem creases of the face such as frontal lines and frown lines, crow's feet, deep nasolabial and perioral folds, and cervical bands may be caused by the aging process, excessive exposure to the sun, disease, or genetic disposition. The condition may become aggravated by habitual hyperkinesia of certain mimetic muscles like the frontalis, corrugators, orbicularis oculi, levatores labii superioris, zygomatici, and the platysma. The diagnosis is established clinically by electromyography and selective muscle and nerve blocks. In these cases we advocate regulation of the mimetic hyperkinesia through selective myotomy, myectomy, and neurotomy of the responsible mimetic muscles (mimetic modulation). These procedures may be performed exclusively or in combination with a blepharoplasty, rhytidectomy, or other procedure. Our experience with 60 patients over the past five years (medium = 3.5 years) is presented. Problems and complications such as paresthesia and hypesthesia, partial paresis and asymmetry, incomplete correction, and recurrences are discussed. We believe that mimetic modulation is a valuable concept in treating problem creases and thereby improves the results of the aesthetic surgery of the face.

Adult↗
PubMed1984

Effects of changes in preoptic temperature on stretch response of muscle spindle endings in the cat's soleus muscle.

The effects of changing the temperature in the preoptic region on the stretch responses of primary and secondary endings of the muscle spindle in the soleus muscle was investigated in urethane anesthetized cats. The local temperature of the preoptic region was controlled by implanting water perfused thermodes (32-42.5 degrees C). A standard ramp and hold stretch stimulus was repeatedly applied to the soleus muscle during changes of preoptic temperature from normal to hypo- or hyperthermic values. During each stretch the instantaneous firing rate was recorded and the static firing frequency and the dynamic index were electronically determined according to Crowe and Matthews (1964). Of a total of 76 investigated muscle spindle afferents, the stretch responses of 49 (65%) were altered by changing preoptic temperature. The static stretch response was increased in all cases during cooling, whereas during preoptic heating the static stretch response increased in about half of the afferents and decreased in the rest. Increase in the static stretch response during both cooling and heating was usually combined with the appearance of spontaneous discharges at rest. With regard to the static stretch response, primary and secondary muscle spindle endings responded similarly to cooling and heating. Two types of preoptic temperature effects on the stretch responses of primary endings were observed. In the majority of afferents only the static stretch response was augmented during cooling, whereas the peak response was little changed resulting in a decrease of the dynamic index ('static' response type).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1978

A comparative study of the cardiac troponin inhibitory factor (TNI) from mammalians.

Troponin inhibitory factor, TNI, was prepared by affinity chromatography from different mammalian hearts. (i) Structure. These different TNI have the same M.W. (28000), which is higher than that found in rabbit skeletal muscle (23000). Nevertheless they differ with respect of their charge as shown by alkaline urea polyacrylamide gel electrophoresis using cardiac TNI which has previously been bound to an excess of skeletal troponin Ca2+-binding factor. These changes do not correlate with the PO4 content of TNI. They are associated with structural differences demonstrated by peptide mapping of the unfolded molecule after papain treatment. The structure of cardiac TNI from rat and rabbit differs clearly from that of crow and pig. (ii) Biological activity. These different TNI have the same inhibitory effect on skeletal actomyosin. ATPase, the same content of PO4 and the same ability to be phosphorylated in-vitro by a bovine heart c-AMP-dependent protein kinase.

Adenosine Triphosphatases↗