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PubMed2000

Regional specialization of Sarcodes sanguinea (Ericaceae) on a single fungal symbiont from the Rhizopogon ellenae (Rhizopogonaceae) species complex.

We have sampled the mycorrhizal roots of 76 snow plants (Sarcodes sanguinea, Monotropoideae, Ericaceae) in two areas of the Sierra Nevada of California that are ∼180 km apart. To identify the fungal symbionts associated with these plants, we first analyzed restriction fragment length polymorphisms (RFLPs) of the internal transcribed spacer region (ITS) of the fungal nuclear ribosomal repeat. Fungal ITS-RFLPs were successfully produced from 57 of the 76 plants sampled, and all symbionts shared the same DNA fragment pattern. The morphology of S. sanguinea mycorrhizae was consistent with that expected from a Rhizopogon species in section Amylopogon. To confirm and refine this identification, a total of six fungal ITS sequences were determined from S. sanguinea mycorrhizae. These sequences were analyzed together with eight existing and eight newly determined ITS sequences from Rhizopogon section Amylopogon. The newly determined sequences include an ITS sequence from the fungal symbiont of pine drops (Pterospora andromedea, Monotropoideae, Ericaceae), a plant that was previously reported to be exclusively associated with the Rhizopogon subcaerulescens group. When these sequences were analyzed together, the Sarcodes symbionts grouped tightly with several collections of R. ellenae including the holotype, one collection of R. idahoensis, and one collection of R. semireticulatus. A different lineage comprised collections of R. subgelatinosus, R. subcaerulescens, another collection of R. semireticulatus, and the Pterospora symbiont. We conclude that S. sanguinea associates exclusively with a single species in the R. ellenae species complex throughout our sampling range. These results indicate a much higher level of specificity in S. sanguinea than was previously reported and confirm the emerging pattern that nonphotosynthetic, monotropoid plants generally associate very specifically with a narrow range of ectomycorrhizal fungi.

Journal Article↗
PubMed2000

[Medical treatment of dystocia in zoo animals].

Kasuistics of Zoo animals with dystocia (Anoa, Giraffe, Snow goat, Scimitar horned Antelope, Bactrian camel, Tiger, Diana monkey) treated with special pharmaceuticals (glukokortikoids, cienbuterol, denaverine, carbetocin) and distance injections by blow darts are introduced. These procedures are described as very effective and save methods of obstetrics especially in Zoo animals.

Animals↗
PubMed2000

[NMDA-Receptors in the central nervous system of the honey bee with kynurenine deficiency].

Effects of some drugs on the short-term memory were tested. In kynurenine deficit, mutant snow laranja manifested the same pharmacological profile and 10 to 100-fold enhancement of sensitivity of the NMDA receptors' different sites. The data obtained suggest that the gene controlling the key enzyme activity of the kynurenine pathway of tryptophan metabolism is involved in regulation of the CNS NMDA receptors' functional condition. The kynurenines may be classified as endogenous modulators of the NMDA receptor sensitivity.

Animals↗
PubMed2000

[Are emergency admissions to medical departments dependent on weather?].

BACKGROUND: It is widely believed that patients are more frequently admitted to hospital in bad weather. MATERIAL AND METHODS: We evaluated all 15,060 emergency admissions to the Medical Department of Rogaland Central Hospital during a 17-month period and compared this material with meteorological data. RESULTS: We found no correlation between the number of admissions and "good weather" (as defined by the amount of cloud cover), but we found a significant difference of about two more patients (6.6%) being admitted on days with rain and snow. There was no correlation between the amount of precipitation and the number of admitted patients, but a small, significant inverse relation between temperature and admissions. We have also demonstrated a considerable difference in the number of admissions on the different weekdays, with the highest number on Mondays and the lowest on Saturdays. INTERPRETATION: Both the incidence of disease and doctor availability may partially explain the influence of weather and the daily variation in emergency admissions to hospital.

Emergencies↗
PubMed2000

[The "two cultures" in medicine].

"The two cultures", a concept launched by C.P. Snow in 1959, points to the schism between science and the humanities, two distinct professional cultures which not only has gone separate ways, but also developed deep tensions between them. Historically, medicine is part of the scientific culture as well as that of the humanities. However, contemporary doctors see themselves first and foremost as scientists, and modern medicine leaves little scope for the tradition of the humanities. Including humanities in medical undergraduate, graduate and continuous education does not necessarily make doctors more humane, but insight in these disciplines may stimulate reflection and broaden their perspective on the practice of medicine. Given the expectations and pressures for efficiency to which doctors and other health care workers are subjected, a greater emphasis on the humanities in medicine may be of help to doctors in coping with their patients, society--and themselves.

Biological Science Disciplines↗
PubMed2000

[The best available explanations].

In 1959, C.P. Snow distinguished between the "two cultures"--the cultures of the natural and the human sciences. Medicine, however, does not and cannot belong to only one of these two cultures. It belongs essentially to both. The reason is that medicine is governed by certain ideals about what characterises a human life in dignity. These ideals define certain basic alternatives for action as immoral, for instance not to attempt to cure illness. This being so, there are certain phenomena which medicine cannot permit itself to ignore, thus it must seek the best available explanations of such phenomena where these explanations are to be found. Often the best explanations are to be found in the human sciences. Medicine needs concepts, theories and methods which enable its practitioners to grasp meaning, to describe social relations and to understand history.

Concept Formation↗
PubMed2000

[Is there a place for humanistic dimension in medical education?].

Inspired by the concept of "two cultures", coined by C.P. Snow, this paper discusses the role of the humanities in relation to the natural sciences in a recently (since 1993) revised medical curriculum at the Faculty of Medicine in Trondheim, Norway. A concept of a "third culture" is identified as well: community medicine in a broad sense, disciplines dealing with health, illness and disease in the context of society and the environment. The implementation of the new curriculum was affected by intended and unintended social forces. The result was a hybrid model rather than the planned "pure" problem-based model. The humanities and "third culture" disciplines tended to yield to the pressure from the basic sciences when numbers of formal lectures were strictly limited, while the basic sciences themselves felt cut short by clinical disciplines. Problem-based learning in groups did seem efficient in basic sciences and clinical subjects, but not for the humanities or third culture disciplines. This apparent limitation in the problem-based approach was probably due to contextual factors, rather than inherent in the method itself.

Concept Formation↗
PubMed1975

A spontaneous neuropathy of free-ranging Japanese macaques.

Thirteen cases of a spontaneous neuropathy were observed among 150 free-ranging Japanese snow monkeys (Macaca fuscata). Necropsy of 4 individuals revealed lesions in the peripheral and central nervous systems. Pathologic changes were associated with ingestion of coyotillo berries (Karwinskia humboldtiana).

Animals↗
PubMed2001

Mediterranean climate effects. II. Conifer growth phenology across a Sierra Nevada ecotone.

Growth and xylem water potential of the lower elevation conifers Pinus jeffreyi and Abies concolor and the higher elevation Pinus monticola and Abies magnifica were monitored in their montane Mediterranean habitat of the southernmost Sierra Nevada mountains of California. Measurements were made across the ecotone between the midmontane and upper montane forests and through light and heavy snowfall years.Radial stem growth, averaging ∼1.5 mm/yr, started 2 wk after snow melt, providing that maximum air temperatures had reached 21°C, and ended when predawn water potentials fell rapidly at the onset of the summer drought. Leader growth started on or after a fixed date, providing that minimum air temperatures were above -4°C for Pinus species or +2.5°C for Abies species. The cue for leader growth was inferred to be photoperiodic. Leader growth ended when either a determinate internode length of ∼1 mm was reached or predawn water potentials fell rapidly. Abies magnifica grew more rapidly than the low-elevation species, but had a shorter growth period; its annual leader growth, as a consequence, was only 35 mm/yr vs. 50 mm/yr for the low-elevation species. Needle growth was similarly determinate in the absence of early drought. This growth phenology contributes to determining species distribution across the ecotone.

Journal Article↗
PubMed1995

The circum-Chryse region as a possible example of a hydrologic cycle on Mars: geologic observations and theoretical evaluation.

The transection and superposition relationships among channels, chaos, surface materials units, and other features in the circum-Chryse region of Mars were used to evaluate relative age relationships and evolution of flood events. Channels and chaos in contact (with one another) were treated as single discrete flood-carved systems. Some outflow channel systems form networks and are inferred to have been created by multiple flood events. Within some outflow channel networks, several separate individual channel systems can be traced to a specific chaos which acted as flood-source area to that specific flood channel. Individual flood-carved systems were related to widespread materials units or other surface features that served as stratigraphic horizons. Chryse outflow channels are inferred to have formed over most of the perceivable history of Mars. Outflow channels are inferred to become younger with increasing proximity to the Chryse basin. In addition, outflow channels closer to the basin show a greater diversity in age. The relationship of subsequent outflow channel sources to the sources of earlier floods is inferred to disfavor episodic flooding due to the progressive tapping of a juvenile near-surface water supply. Instead, we propose the circum-Chryse region as a candidate site of past hydrological recycling. The discharge rates necessary to carve the circum-Chryse outflow channels would have inevitably formed temporary standing bodies of H2O on the Martian surface where the flood-waters stagnated and pooled (the Chryse basin is topographically enclosed). These observations and inferences have led us to formulate and evaluate two hypotheses: (1) large amounts of the sublimated H2O off the Chryse basin flood lakes precipitated (snowed) onto the flood-source highlands and this H2O was incorporated into the near surface, recharging the H2O sources, making possible subsequent deluges; and (2) ponded flood-water in Chryse basin drained back down an anti basinward dipping subsurface layer accessed long the southern edge of the lake, recharging the flood-source aquifers. H2O not redeposited in the flood-source region was largely lost to the hydrologic cycle. This loss progressively lowered the vitality of the cycle, probably by now killing it. Our numerical evaluations indicate that of the two hypotheses we formulated, the groundwater seep cycle seems by far the more viable. Optimally, approximately 3/4 of the original mass of an ice-covered cylindrical lake (albedo 0.5, 1 km deep, 100-km radius, draining along its rim for one quarter of its circumference into substrata with a permeability of 3000 darcies) can be modeled to have moved underground (on timescales of the order of 10(3) years) before the competing mechanisms of sublimation and freeze down choked off further water removal. Once underground, this water can travel distances equal to the separation between Chryse basin and flood-source sites in geologically short (approximately 10(6) year-scale) times. Conversely, we calculate that optimally only approximately 40% of the H2O carried from Chryse can condense at the highlands, and most of the precipitate would either collect at the base of the highlands/lowlands scarp or sublimate at rates greater than it would accumulate over the flood-source sites. Further observations from forthcoming missions may permit the determination of which mechanisms may have operated to recycle the Chryse flood-waters.

Disasters↗
PubMed2001

[Characteristics of N2O emissions from vegetal soils on Fildes peninsula, Antarctica].

The N2O fluxes from the vegetal soils were first measured on the Fildes peninsula, Antarctica, and the total N2O emission was also estimated in the summer 2 months. The daily variations of N2O fluxes appeared single-peak trend under the sunshine or rainy weather conditions but they were irregular under the snow weather conditions and inconsistent with the atmospheric temperatures. The seasonal variations of the N2O fluxes were affected by the temperature and rainfall. The conditions during the transitions between dry and wet seasons improved the N2O emission. The total N2O emissions from moss and lichen soils were 3.7152 kg and 2.5344 kg, respectively. It follows that the vegetal soils are the sources for the atmospheric N2O on the Fildes peninsula, Antarctica.

Antarctic Regions↗
PubMed2001

"Side balloon stenting": a novel technique for bifurcation lesions.

We describe a new technique to treat stenoses of coronary bifurcations. The aim of this technique, called "side balloon stenting," is to treat the bifurcation lesions with the kissing balloon technique, implanting one or more stents without removing the guidewires which remain in place during the whole procedure, avoiding potential problems of access to the vessels jailed by stent struts. In addition, implanting the stent using the kissing balloon technique would prevent the "snow-plow" phenomenon (plaque shifting) in the side branch. The "side balloon stenting" technique was applied in 29 cases at various levels of coronary artery segments involving bifurcations (Table 1). The technical success rate of the side balloon stenting was 90% (25 procedures). The elective placement of one stent in the main vessel was done in 20/25 procedures (80%), and in only 5/25 (20%), it was also necessary to insert a second one in the side branch (due to suboptimal results), using the "culotte" technique in two and the T-technique in the other three. We were unable to advance the system to the right position in 4 patients (13%): in 2 due to twisting of the guidewires and in the other due to vessel tortuosity and insufficient backup of the system (guiding catheter and guidewires). In these four last cases, the delivery system was retrieved and a stent was successfully implanted in the right position in the main branch. Angiographic success (residual stenoses < 30% and TIMI 3 flow in both branches) was obtained in 100% of the cases. The post-intervention period was uneventful. These preliminary results show that the side balloon stenting technique is both feasible and safe in th treatment of coronary bifurcations with a satisfactory rate of procedural success and often (82%) positioning only one stent in the parent vessel, thus avoiding stenting the side branch. It will be necessary, however, to assess, based mainly on restenosis rate, whether these promising immediate results will persist in the long run.

Angioplasty, Balloon, Coronary↗
PubMed1996

Science and culture in mid-Victorian Britain: the reviews, and William Crookes' Quarterly Journal of Science.

Charles Darwin's Origin of Species was published in 1859, and we are often disposed to see it as marking an epoch in the struggle between religion and science. Recent analyses especially of the part played by T. H. Huxley, 'Darwin's bulldog', emphasise instead (or as well) Huxley's aim to exclude affable 'gentlemen of science' from what was becoming a profession for experts. Evidence from the Reviews of the period show that science accounted for some 10% of the articles; but also that demand for this very general literature was falling, as science and humanities indeed grew apart into what C.P. Snow later called 'two cultures'.

History, 19th Century↗
PubMed1997

[Vicar's daughter died of cholera after drinking salt sea water].

In 1850 a vicar's daughter wanted to cure her lymphadenitis by health sea baths and drinking strengthening salt sea water. In the morning of the eleventh of August she took a bath and emptied three glass of salt sea water. At about 3 hours P.M. she fell ill with intensive watery diarrhoea and died on the following morning at 8 o'clock. Within one month 9 per cent of the population in the port of Malmo fell ill with cholera which killed every third of those affected. Necropsies were performed on some cases but did not reveal any remarkable changes. At the same time cholera attacked Lubeck and other ports of the Baltic sea. The sudden onset and the failure of quarantine precautions suggested intoxication of miasmic orgin. Thus the Swedish Medical Health authorities concluded that the disease was caused by atmospheric and telluric disturbances. Representatives of the Church opposed and considered that the disease was contagious. In 1883 Robert Koch discovered the cholera vibrion. Since then cholera has been considered as an intestinal infection. Cholera was supposed to affect only man, because it was not possible to transfer it to animals. Max von Pettenkofer disapproved the idea of contagiosity. He ingested cholera vibrions without falling ill. Recent findings have confirmed that there is need for at least one hundred billion of vibrions to cause clinical symptoms, whereas only 25 microgram of the toxin is required to produce intensive diarrhoea. Unlike true enteric bacteria, the cholera vibrions prefer aerobic conditions. They do not invade the tissues, and unlike dysentery, cholera disease does not induce inflammatory reactions. In 1855 John Snow proved that cholera was spread by water. All cholera outbreaks in Sweden have been associated with sea ports or inland seaways. Recent investigations have revealed that cholera vibrions are free-living planktonic organisms in sea water in many parts of the world. Human activities may help to spread the vibrions. Man is attacked by their toxin, but the infection takes place in the sea water rather than in the human gut. This is well illustrated by the present sad case report which was described without comments in the contemporary official medical report.

Balneology↗
PubMed1994

[Ophthalmology in Greenland from the year 1000 until the year 2000].

The superstition of the Eskimoes exists even today also with regard to disease and treatment. The author has experienced this himself as ophthalmologist in Greenland. Snow blindness is a common complaint in Greenland and different types of primitive snowglasses to protect the eyes are described. Primitive eye operations were performed by the Eskimoes as long as 250 years ago. In 1721 Denmark commenced a colonization of Greenland when the missionary Hans Egede was sent there. The first physician arrived in Greenland in 1742 but was only there for 2 years. The next one was sent 18 years later. Since then innummerable physicians have worked for Greenland for shorter and longer periods. The observations of several doctors who have seen eye diseases among the Eskimoes are mentioned. During the past 70 years eye specialists have regularly visited the country and by screening and the following treatment helped many with eye lesions.

Greenland↗
PubMed2001

Betahistine in the treatment of vertigo. History and clinical implications of recent pharmacological researches.

A short profile of betahistine and its activity in treatment of Menière's disease and other forms of peripheral vertigo is presented. The clinical efficacy of betahistine is documented by a series of more than twenty controlled clinical studies, performed in the years 1966-2000. Basic researches initially proved that bethaistine acts trough a vasodilating action on inner ear and cerebral blood flow (Suga and Snow, 1969; Martinez, 1972). In the following years this activity was confirmed using the modern laser doppler flowmetry technique (Laurikainen et al, 1998). Further recent studies proved that betahistine acts on the central vestibular histaminergic system as a weak H1 agonist and a strong H3 antagonist (Arrang et al., 1985), improving the process of vestibular compensation (Tighilet et al., 1995) as well as on peripheral labyrinthine receptors, reducing the spontaneous firing rate but not the activity induced by thermal or mechanical stimulation (Botta et al., 1998). More than forty years after its discovery, this series of studies carried out in the second half of the 90s leads to the conclusion that betahistine is a drug which maintains its scientific interest and its pharmacological potential in the treatment of vertigo.

Betahistine↗
PubMed2001

Mucus fishing syndrome: case report and new treatment option.

BACKGROUND: Mucus fishing syndrome (MFS) is a cascading cyclic condition characterized by continuous extraction of mucous strands from the eye. It is usually initiated by ocular irritation. In response to irritation, ocular surface cells produce excess mucus. A "snow balling" cycle begins when the patient extracts ("fishes") excess mucus from the ocular surface, thereby causing further irritation and a more-profound mucous discharge. To date, treatment includes eliminating the initiating element and educating the patient not to touch the eye when extracting the excess mucus, CASE REPORT: Presented is a case of mucus fishing syndrome initiated by dry eye. The patient's diagnosis, MFS, was identified by persistent mucous discharge, his admittance and demonstration of digitally extracting mucus from the ocular surface, and a characteristic rose bengal staining pattern. The conventional treatment initiated by using artificial tears for the dry eye condition and educating the patient not to touch the ocular surface did not provide relief from the excess mucous discharge. Therefore, a new approach to treatment was pursued. In order to break the cycle, a mucolytic agent and an antihistamine-mast cell stabilizer were prescribed, until the ocular surface healed. After treatment, the patient reported alleviation of symptoms and demonstrated improvement in ocular surface integrity by a profound reduction in rose bengal staining. CONCLUSION: Mucus fishing syndrome is challenging to resolve with conventional treatment because it requires a certain level of psychological tolerance and perseverance from the patient. By eliminating the present mucus and diminishing mucous production pharmacologically, the practitioner is able to remove the stimulus for digital extraction and thus accelerate ocular surface healing. We present a proposed new treatment option for patients who are refractory to conventional treatments.

Cystine↗
PubMed2001

Runoff of acidic substances that originated from atmospheric deposition on Yakushima Island, a world natural heritage site.

In this paper we present monitoring data of stream waters that may reflect acidic impacts on the island as well as the rainwater qualities. The pH ranges of the river water in the Kawara streams in the western part of the island and the Yodogo stream in the central part of the island were 5.71-6.35 and 5.85-6.12 during 1992-1999, respectively. The concentrations of SO4(2-) and NO3- in the river water were lower than those in the rainwater. Many differences were observed among the sampling sites. Higher concentrations of acid substances are found in the stream waters of the western area compared to the other areas. On the other hand, sulfuric acid is the major acid in the rainwater, snow and rime ice. No differences were observed in the ion constituents of the rainwater collected in the areas. These results suggested that the densely growing canopy may play a role in holding air pollutants, and acidic substances deposited on the canopy would be discharged as a through-fall and a stem flow. Furthermore, the water mass containing high ionic substances in the western area has been held in the groundwater layer, continuously supplying the stream waters during dry weather days. On the other hand, part of the basic runoff will be diluted with a surface runoff during the rainy days. As a result, the concentrations of the ionic substances in the stream waters during rainy days decreased.

Acid Rain↗