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The frequency of reproduction and homing success are crucial in determining the lifetime reproductive fitness of iteroparous salmonids. We examined consecutive spawning and homing by Sakhalin taimen (Parahucho perryi), one of the least-studied iteroparous salmonids. The average consecutive return rate was 69.5%, the highest ever reported for an iteroparous salmonid. The consecutive return rates were highest for large spawners, females, and individuals with active inter-tributary movements in the preceding year. We estimated tributary-scale repeat homing rates to be 50–87%, which was significantly higher than expected by chance alone. The repeat homing rates were higher for spawners that entered tributaries with more abundant spawners in the preceding year, which is consistent with the pheromone hypothesis because the abundance of spawners in a tributary is expected to correlate to the concentration of chemical homing cues emanating from offspring in the following year. These extremely high consecutive return and homing rates likely facilitated local adaptation over evolutionary time scales and have contributed to population stability in this river system. These same traits, however, may impede species recovery following habitat restoration efforts within the species historic range (e.g. dam barrier removal or improved passage) due to their limited rate of dispersal. more...

The conservation of land-locked populations of migratory fishes is increasingly important in the era of dam removal and habitat reconnection. We used an otolith strontium (Sr) tracer (87Sr/86Sr) to test the hypothesis that a land-locked population of an endangered salmonine species, Sakhalin taimen (Parahucho perryi), retains the capacity for anadromy, and that some individuals out-migrate from the reservoir to the sea. Years later, these individuals return but are blocked by the migration barrier of the reservoir dam and are denied reproduction in their natal streams. Juvenile taimen collected from the reservoir and two nearby regions were classified based on their otolith Sr isotopic signatures to their regions of origin with an overall accuracy of 88%. When the same classifier was applied to ocean-caught adult taimen, we predicted some individuals had originated from the reservoir with high posterior probabilities (> 0.9). Whether the land-locked Sakhalin taimen can help sustain the metapopulation dynamics of the species at the watershed scale may depend on whether, and how soon, the disrupted migration pathway is restored. more...

Four combinations of fish and prawn species were stocked in organic rice–fish systems to examine their growth performance, feeding habits, competitive interactions, and food-web structure. The species combinations were: (I) three fish species commonly stocked in rice–fish systems in the Lower Mekong countries, namely Barbonymus gonionotus, Cyprinus carpio, and Oreochromis niloticus; (II) the same three species plus the giant freshwater prawn Macrobrachium rosenbergii; (III) three herbivorous fishes native to the Mekong River, namely B. gonionotus, Barbonymus schwanenfeldii, and Cirrhinus microlepis; and (IV) the herbivorous and omnivorous fishes B. gonionotus, C. microlepis, and Trichogaster pectoralis, together with the carnivorous fish Channa striata. Growth performance was examined using specific growth rate (SGR), and feeding habit was examined through stomach content and stable isotope (carbon and nitrogen) analyses. All fish and prawn species exhibited SGRs of roughly 1–2% d−1 except for C. striata, which had a slower growth rate ( more...

Understanding the proximate factors and mechanisms driving primary production in manmade reservoirs is crucial because such production can translate into added fish yields that provide people with food and livelihoods. Furthermore, reservoir fish production could potentially compensate for the loss of fish yields due to habitat fragmentation and alterations caused by damming and impoundment. We monitored primary production, identified environmental factors responsible for its variability, and examined the relationship between primary production and fish production in nine large water bodies of the Lower Mekong Basin for 2 years. The estimated primary production ranged from 40 to 302 g C/m2/y and was generally greater in the wet season than in the dry season. Linear mixed-effects modelling identified the concentration of dissolved inorganic carbon as a significant fixed-effect variable regulating primary production, after variability due to random and fixed effects of water body and seasonality, respectively, were taken into account. Fish yields marginally increased with increasing primary production across the water bodies, with the estimated energy transfer efficiency ranging from 0.004 to 0.009. Dissolved inorganic carbon was partly determined by the lithological composition of the water body catchment, suggesting that the geographic locations of proposed dams determine the magnitude of primary production and hence future fish production. more...

The assemblage patterns of larval fishes from three neighboring tributaries viz., Songkram, Gam and Mun of the Mekong River in Thailand were investigated between August 2009 and June 2010. These rivers interact with their floodplains, which are important spawning and nursery grounds for the Mekong fishes. There is no dam along the Songkram River; meanwhile the Gam River has several irrigation dams with a fish ladder at each dam site and the Mun River has a hydropower dam with a fish ladder and sluice gates that are opened during the wet season each year. A total of 97 fish species were collected from the study sites. Assemblage of Gam River was dominated by larvae of resident, black fish species. Assemblage of Mun River during sluice gate opening scheme was similar to that of Songkram River during wet season. Assemblage during flood period of Songkhram River showed the most diversity and abundance of migratory, white fish larvae. Conservation of integrity of the floodplain-river system of Songkhram River is among the crucial strategies for sustaining fish diversity and fisheries in the Lower Mekong River Basin. more...

Diversity and community structure of fishes were studied in three neighbouring tributaries of the Mekong River in Thailand, namely the Mun, Songkhram and Gam Rivers. The rivers are located in the same ecoregion but have contrasting levels of both hydrological regulations and mitigation measures; the Mun River has a hydropower dam with a fish ladder and sluice gates that are opened during the wet season each year, the Gam River has several irrigation dams with a fish ladder at each dam site, and the Songkhram River has no dams along its river course. A total of 124 freshwater fish species were sampled in these rivers from August 2009 to June 2010. Overall species richness was highest in the Songkhram River (112), followed by the Mun (97) and Gam (54) Rivers. Average per site species richness was also significantly different among rivers but not among sampling months. Abundance–biomass comparison plots revealed considerably overlapping distributions of these two metrics from the dry to early rainy seasons in the Songkhram River and, to a lesser extent, in the Mun River. Fish assemblage data were classified into six clusters with similar community structure. Fish assemblages in the Gam River constituted a single cluster, while those in the other two rivers formed multiple clusters depending on the sampling season. The results of the cluster analysis are discussed in relation to the dominance of the three migration guilds (white, black, and grey fishes) of the Mekong River fishes. The effectiveness of the mitigation measures was determined to be limited in alleviating adverse impacts of dams in these tributaries of the Mekong River. Copyright © 2014 John Wiley & Sons, Ltd. more...

Sakhalin taimen (Parahucho perryi) range from the Russian Far East mainland along the Sea of Japan coast, and Sakhalin, Kuril, and Hokkaido Islands and are considered to primarily be an anadromous species. We used otolith strontium-to-calcium ratios (Sr/Ca) to determine the chronology of migration between freshwater and saltwater and identify migratory contingents of taimen collected from the Koppi River, Russia. In addition, we examined taimen from the Sarufutsu River, Japan and Tumnin River, Russia that were captured in marine waters. Transects of otolith Sr/Ca for the Sarufutsu River fish were consistent with patterns observed in anadromous salmonids. Two fish from the Tumnin River appeared to be recent migrants to saltwater and one fish was characterized by an otolith Sr/Ca transect consistent with marine migration. Using these transects as benchmarks, all Koppi River taimen were classified as freshwater residents. These findings suggest more work is needed to assess life history variability among locations and the role of freshwater productivity in controlling migratory behavior in taimen. more...

The Sakhalin taimen Parahucho perryi is an endangered salmonid with a natural range limited to the Russian Far East and Japan. We constructed a classification tree to determine the environmental factors shaping the historical global distribution of this species and then predicted its potential geographic range. The distribution was most strongly influenced by a spatial autocorrelation term, indicating that it is highly contiguous. Large drainage basins with low topographic relief and large floodplains had a higher probability of taimen occurrence. The boundary of the global distribution was delineated by mean monthly precipitation within the range of 54–96 mm. The presence of Sakhalin taimen was predicted in many drainage basins where it has never been recorded. We also modeled the status of 48 taimen populations in Japan, where it was possible to classify them into three categories: currently stable (7), endangered (5), and extinct (36). The most significant factor differentiating the 12 extant ... more...

Rainbow trout introduced into Hokkaido in 1920 have become widely distributed due to extensive release into many reservoirs and lakes for sport-fishing; their presence often results in reductions of native fish populations. We analyzed and predicted the relationship between the probability of occurrence of rainbow trout and the proximity of dams (or attributed reservoirs), using a database of the presence or absence of rainbow trout collected during 1960–2004 in Hokkaido to clarify the spread patterns of exotic species (e.g., rainbow trout) due to large-scale damming over a long period. Rainbow trout were abundant in streams within approximately 10 km of dams in recent years, regardless of whether the stream was up- or down-stream from the dam and after accounting for the effects of other environmental variables (e.g. elevation, population density, and survey year). A delayed increase in trout occurrence below dams as compared with above dams suggests that the occurrence below dams may be largely due to escapement of stocked populations and a continuously increasing abundance since 1970. The management of dams and reservoirs is necessary to prevent further spread of rainbow trout because they can threaten habitats of native Japanese salmonids through various mechanisms. more...

We analyzed the patterns of total, endangered and exotic fish species richness in 80 reservoirs throughout Japan using Generalized Linear Models (GLMs) with variables of dam characteristics (e.g. reservoir size, isolated period, altitude, DO, pH, rainfall, and air temperature) and watershed characteristics (e.g. watershed area, human population, and land-use patterns). Exotic species richness was positively correlated with total species richness but negatively correlated with endangered species richness. Largemouth bass, rainbow trout, and bluegill were the three most widely distributed species, occupying 47.5, 37.5, and 33.8% of the reservoirs, respectively. The patterns of total and endangered species richness were largely explained by watershed area and annual air temperature. Exotic species richness was determined primarily by the proportion of developed areas within each watershed. Therefore, reservoirs in more developed areas tend to support more exotic fish species that in turn threaten endangered fish species more severely. more...

We examined the effects of dams on freshwater fish species based on data collected during 1990–2004 from 200 drainage systems in Japan. Of the 76 fish species examined, the occurrence of 20 species within Petromyzontidae, Cyprinidae, Cobitididae, Salmonidae, Cottidae, and Gobiidae was negatively affected by the presence of dams located in the downstream reaches of fish survey sites, whereas the occurrence of 12 species within Cyprinidae, Adrianichthyidae, Centrarchidae, and Gobiidae was positively associated with the presence of dams. A significantly higher proportion of the fishes with a negative damming effect were diadromous species as compared to the fishes with a positive damming effect. Conversely, the latter group had a significantly higher proportion of nonnative species than the former. A significant interaction existed between the effects of damming and the effects of elevation on family-specific species richness. Families dominated by native migratory species showed a greater reduction in the number of species above dams at lower elevations, whereas families represented primarily by nonnative species had higher species richness above dams at higher elevations, except for Centrarchidae, which was always higher in species richness above dams regardless of elevation. Based on our findings, dams in Japan have adversely affected native freshwater fishes by blocking their migration routes, favoring nonnative fishes, or altering existing habitats. more...

Quasi-continuous DO and pH measurements (total 47 days) were conducted during enclosure experiments (6 enclosures; 5 × 5 × 2.5 m), in which a biomass gradient of silver carp was created. After subtracting the air–water exchanges of O2 and CO2, the chemical and biochemical changes in DO (dissolved oxygen) and DIC (dissolved inorganic carbon) were estimated in order to evaluate MQ (metabolic quotient: DO change divided by DIC change) at intervals of 1 hour. By removing small absolute changes below the threshold value (0.01 mM h−1), the averaged values of the 24 MQ means for the respective 1-hour periods ranged from 0.96 to 1.20 in the six enclosures. Because the MQs in the daytime inversely correlated well with the ratio of NH+ 4–N to (NH+ 4–N + NO− 3–N), not the ecosystems, i.e., density of fish, community structure of zooplankton and phytoplankton, but the form of nitrogen uptaken for primary production principally determined the MQs. The higher MQs observed in the daytime compared with the nighttime (from 14% to 21% except 3% for one enclosure) could not be explained by the denitrification and/or dissolution of CaCO3 in the sediments, therefore suggesting the selectively faster decomposition of part of the organic matter provided through primary production, in other words, an accumulation of another part of the organic matter in the diurnal and/or daily time scale. more...

We investigated aquatic macrophytes, water quality, and phytoplankton biomass and species composition in three shallow lakes with different levels of vegetation cover and nutrient concentration in Kushiro Moor, during August 2000. Trapa japonica can live in a wide range of nutrient levels. This species forms an environment with a steeper extinction of light, higher concentrations of dissolved organic carbon (DOC), lower concentrations of dissolved oxygen (DO) near the bottom, and lower concentrations of nitrate + nitrite and soluble reactive phosphorus (SRP) than other vegetation types. The pH was much higher in a Polygonum amphibium community, and the DO near the bottom did not decrease compared to a T. japonica community in the summer. The relationship between chlorophyll a and the limiting nutrient (total phosphorus (TP) when total nitrogen (TN) : TP is ≥10 and TN/10 when TN : TP is more...

A link between stream geomorphology and lotic ecosystems was demonstrated by quantitatively examining the precise locations of salmonid redds with respect to the planform geometry of streams using a differential global positioning system. A total stream distance of 59 km was surveyed in 17 streams, in which a total of 309 redds of Sakhalin taimen (Hucho perryi) were recorded. The average size (±sd) of these redds was 227 ± 60 cm in length and 122 ± 42 cm in width. A meta-analysis of these data showed that channel sinuosity was significantly greater at sites where Sakhalin taimen redds were constructed than the average stream sinuosity. This salmonid preference for highly sinuous reaches was detected when the sinuosity index was calculated at 50-m increments and became insignificant at greater distance increments. This habitat–sinuosity relationship will be more pronounced in streams with only moderately sinuous channels, less abundant large woody debris, and higher spawner densities. more...

(2000). The responses of an aquatic ecosystem to the manipulation of the filter-feeding silver carp (Hypophthalmichthys molitrix) SIL Proceedings, 1922-2010: Vol. 27, No. 2, pp. 1033-1039.

1. We conducted enclosure experiments in a shallow eutrophic lake, in which a biomass gradient of the filter-feeding planktivore, silver carp, Hypophthalmichthys molitrix Valenciennes, was created, and subsequent community changes in both zooplankton and phytoplankton were examined. 2. During a summer experiment, a bloom of Anabaena flos-aquae developed (approximate to 8000 cells mL(-1)) solely in an enclosure without silver carp. Concurrent with, or slightly preceding the Anabaena bloom, the number of rotifer species and their abundance increased from seven to twelve species (1700-14 400 organisms L-1) after the bloom in this fish-free enclosure. Protozoans and bacteria were generally insensitive to the gradient of silver carp biomass. 3. During an autumn experiment, on the other hand, large herbivorous crustaceans were more efficient than silver carp in suppressing the algae, partly because the lower water temperature (approximate to 24 degrees C) inhibited active feeding of this warm-water fish and also formation of algal colonies. Heterotrophic nanoflagellate and bacterial densities were also influenced negatively by the crustaceans. 4. Correspondence analysis (CA) was applied to the weekly community data of zooplankton and phytoplankton. A major effect detected in the zooplankton community was the presence/absence of silver carp rather than the biomass of silver carp, whereas that in the phytoplankton community was the fish biomass before the Anabaena bloom, but shifted to the presence/absence of the fish after the bloom. more...

Spatiotemporal distributions and microhabitat use of pink salmon Oncorhynchus gorbuscha and sockeye salmon O. nerka were studied in Lake Creek, southeast Alaska, during three spawning seasons. Sockeye salmon migrated approximately 1 week earlier than pink salmon and spawned 250–350 m upstream from pink salmon. Habitat overlap measured with proportional similarity index monotonically increased with increasing spawner densities. Multidimensional niche spaces measured with water depth, current velocity, and channel gradient at redds were significantly different between pink and sockeye salmon (P < 0.005, Hotelling's T 2-test). However, classification of the redds into individual species was subjected to large error rates; 33% of 70 pink salmon redds and 34% of 125 sockeye salmon redds were misclassified. Competitive interaction between pink and sockeye salmon was not demonstrated. more...

The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus), two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr) and barium (Ba) showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed. more...

Variation in stream life, spawning efficiency, and spawning habitat among adult pink salmon (Oncorhynchus gorbuscha) in the Auke Lake system, southeastern Alaska, was best explained by stream discharge, stream temperature, and a combination of stream temperature and discharge. We estimated these attributes of female pink salmon spawners in samples of daily cohorts tagged as they entered fresh water and used generalized linear models to analyze variation in the attributes with respect to environmental factors. Spawners varied in stream life (5-11 days), spawning efficiency (30-70% of females in daily entry cohorts retained less than 500 eggs at death), and spawning habitat (30-70% spawned in the lake outlet stream rather than the lake inlet stream). Observed variation of habitat (proportionately more use of the cooler inlet stream early in the spawning season when stream temperatures are warm and development is rapid) would contribute to synchronicity of fry emigration, which is known to be positively correlated with subsequent survival in Auke Lake pink salmon. more...

In conservation biology, spatially explicit models, sometimes known as predictive habitat distribution models (Guisan and Zimmermann 2000), have been widely used to predict distributions of plants (Leathwick 1998), insects (Lobo and Martin-Piera 2002; Gutierrez et al. 2005), amphibians (Ray et al. 2002), reptiles (Fisher et al. 2002), fishes (Joy and Death 2001; Leathwick et al. 2005), birds (Peterson and Robins 2003), and mammals (Carroll et al. 1999). This modeling technique has been applied to Japan’s freshwater ecosystems: for example, to reconstruct historical global distribution of an endangered fish species with an already diminished distribution range (Fukushima et al. 2011) and to predict potential areas susceptible to invasion by exotic fish species (Iguchi et al. 2004). Because spatially explicit modeling is a correlative statistical technique, it basically requires only two sets of data: response and predictor variables. What makes this modeling technique different from classic techniques is that the variables (1) are spatial in nature, (2) are most often observational rather than designed, and (3) are not repetitive in space because the earth is the only unit (Cressie 1993). In a field-based ecological study, it practically means that the data are geo-referenced in a given landscape (e.g., by a global positioning system, or GPS). more...

The Mekong River is one of the great rivers of the world and is characterized by high fish biodiversity (Valbo-Jorgensen et al. 2009). The Mekong region is in fact a fish biodiversity hotspot whose richness is only now being revealed. During the last decade more than 279 new species of fish have been discovered in this basin alone (WWF 2009). An analysis of fish species present in 204 rivers worldwide recorded in FishBase (www.fishbase.org) (Fig. 1) and backed by a scientific study or publication. Baran (2010) recently showed that the Mekong River is the second richest river in the world for its fish diversity, after the Amazon River. more...

Identifying and quantifying relationships among landscape patterns, anthropogenic disturbances, and aquatic ecosystems is a new and rapidly developing approach to riverine ecology. In this review, we begin by describing the policy and management drivers for landscape-scale riverine research and we synthesize the technological advances that have enabled dramatic progress in the field. We then describe the development of landscape-scale riverine research through a series of landmark theoretical and review papers. Focusing on landscape-fish relationships, we consider the degree to which past efforts have been successful at meeting three challenges: (1) Has new research effectively incorporated the strengths of new technologies or are we doing the same old thing with more expensive data? (2) Have we incorporated key concepts from landscape ecology to improve our understanding of how landscapes affect rivers? (3) Have we been able to use landscape analyses to address management and policy needs? We conclude with a review of opportunities for advancement in the field of landscape-scale riverine research. These include moving toward the development of mechanistic theories of how landscapes affect rivers across disparate regions; considering the spatio-temporal structure of human impacts to landscapes; harnessing new statistical tools; and carefully defining landscape and response metrics to capture specific features. more...

A Japanese woman with condyloma acuminatum of the urinary bladder is presented. The condyloma acuminatum lesion was resected endoscopically and human papillomavirus 6/11 DNA was detected. After treatment, there has been no recurrence of the disease. more...

A simple method has been developed for detecting a broad range of genital human papillomavirus (HPV) types using the polymerase chain reaction (PCR). We utilized two consensus sequence primer pairs within the E6 and E7 open reading frames to amplify HPV DNA; malignant HPV DNA (from HPV-16, -18, -31, -33, -52b and -58) was amplified using the pU-1M/pU-2R primer pair whereas benign HPV DNA (from HPV-6 and -11) was amplified using the pU-31B/pU-2R primer pair. Identification of the amplification product was confirmed by restriction enzyme digestion. In this study, a pU-1M/pU-2R-mediated PCR was successfully applied to 39 cervical carcinoma specimens; HPV-16 was detected in 19 cases, HPV-18 in five cases, HPV-31 in two cases, HPV-33 in two cases, HPV-52b in one case, HPV-58 in three cases, and an unknown type(s) was detected in four cases. Overall, the prevalence of HPV was 84.6%. The results indicate that this detection system is useful for the detection of HPVs not only of known types but also of new types. more...

Ninety-two cervical scrapes and tissues, obtained from cytologically or histologically normal cervices of Japanese women, were examined for the presence of human papillomavirus (HPV) 16, 18 and 33 DNA by the polymerase chain reaction (PCR) method. Five out of 92 cases were HPV 16 DNA-positive, but neither HPV 18 nor 33 DNA was detected. The HPV (type 16, 18 and 33) prevalence rate in pregnant women, including postpartum, was 10% (3/31), which was higher than that in non-pregnant women. In two HPV 16-positive cases, we detected HPV 16 DNA again 2 months later. HPV (type 16, 18 and 33) prevalence in normal cervices was shown to be relatively low. However, it is very important to follow up the HPV-positive cases in cytologically normal cervices in order to elucidate the relation between HPV infection and the progression of cervical cancer. more...

We have established a highly sensitive method for specific detection of human papillomavirus (HPV) 16, 18 and 33, by using the polymerase chain reaction (PCR). A HPV‐related sequence (140 bp) in the E6 transforming region was specifically amplified and detected by gel electrophoresis and by the use of a specific oligonucleotide probe. The PCR could detect 10‐5–10‐6 copies per cell (maximum sensitivity). Furthermore, HPV 16, 18 and 33 DNAs were synthesized in a common reaction solution and specifically detected by HPV type‐specific probes. The PCR detected the HPV sequence from tissues which were negative to Southern hybridization. This detection technique may contribute significantly to the precise analysis of HPV in small proliferative lesions in the cervix. more...

Variation in the nucleotide sequence of the HPV 16 E7 gene in preinvasive cervical intraepitherial neoplasia (CIN) and invasive cervical carcinoma specimens was analyzed. Direct DNA sequencing of PCR-amplified products with primers different from those used for PCR with 5'-end labeling generated distinct sequence ladders with a low background, even in specimens containing relatively low copy numbers of HPV. Of 14 cervical neoplasias, 11 cases showed sequence diversity from prototype HPV16, and a total of 22 nucleotide exchanges were detected. Nine of these led to single amino acid exchanges: [Thr5] to [Lys5] in one case and [Asn29] to [Ser29] in eight cases. The [Ser29] E7 was distributed uniformly among invasive carcinomas and precancerous legions, and was also found in a normal cervix. The [Lys5] E7 and [Ser29] E7 had transforming potential similar to the prototype E7 assessed by cooperation with the activated ras gene in rat embryo fibroblasts. more...

Using in situ hybridization, human papillomavirus (HPV 6, 16, 18, 31, 33) DNAs were detected in a cervical severe dysplasia accompanied by squamous metaplasia. It was found that, only HPV 31 DNA was harbored in the cervical severe dysplasia, but HPV DNAs were not identified in a lesion of squamous metaplasia. The in situ hybridization method will be of use, therefore, when dysplasia with squamous metaplasia or other lesions are examined for HPV DNA. In a cervical smear, HPV 31 DNA could be detected on the nuclei of dysplastic cells, so this method is applicable to cervical smears. If squamous metaplasia is to be considered as a precursor lesion to cervical dysplasia, the HPV DNA harbored in the dysplasia must also be detected in the accompanying squamous metaplasia. Our results suggested that not all squamous metaplasias were involved with HPV, as far as we were able to detect using five types of HPV DNA probe. more...

HPV-16 and HPV-18 DNA sequences were detected in a case of minimal deviation adenocarcinoma (MDA), a rare pathological type of uterine cervical cancer. This result suggests HPV to be associated with MDA as well as with other pathological types of cervical cancer. more...

Urological tumors were examined for the presence of human papillomavirus (HPV) DNA by using Southern blot hybridization. In 20 male patients with condyloma acuminatum, HPV type 6 was found at 85% (17/20), HPV type 11 at 95% (19/20), HPV type 16 at 5% (1/20) and HPV type 18 at 0% (0/20). In 2 female patients with condyloma acuminatum, HPV types 6, 11, 16 and 18 were found at 100% (2/2), 100% (2/2), 50% (1/2) and 0% (0/2), respectively. All 6 of the patients who were positive for HPV type 6, were also positive for HPV type 11. Two patients were positive for HPV types 6, 11 and 16, the last of which was frequently found in penile cancer and uterine cervical cancer. In 6 patients with penile cancer, two patients were positive for HPV type 16 and negative for HPV types 6, 11 and 18. The remaining 4 patients were negative for all these HPV types. One patient who was positive for HPV type 16 had penile cancer after three previous episodes of penile condyloma acuminatum. From this information, a malignant change in the condyloma acuminatum was assumed to indicate the possible association of HPV type 16 with the process of malignant degeneration. HPV types, 6, 11, 16 and 18 were not detected in a female patient with vulvar cancer. Although HPV was thought to participate in the development of urological tumors except for external genital tumors, all patients examined, consisting of 2 with benign prostatic hypertrophy, 5 with prostatic cancer and 24 with bladder cancer, were negative for HPV types 6, 11, 16 and 18. Eight patients with bladder cancer were negative for HPV type 33. more...

われわれは管理職者グループを対象に過去12年間にわたり健康管理を行なっているが, このグループ内における広範囲胃切除例の遠隔成績について年代別に比較検討し, 高年者群に対する術後管理上の注意などについて考察した.症例は広範囲胃切除術後1年以上6カ月間隔で定期的に術後管理をうけている72例である. 年代分布は40歳代以下18例, 50歳代28例, 60歳代以上26例で, 性別は男性71例, 女性1例, 術式はビルロートI法71例, ビルロートII法1例である. 原胃疾患は進行胃癌5例, 早期胃癌16例, 胃潰瘍23例, 十二脂腸潰瘍6例, 胃ポリープ15例, 胃炎6例, その他1例である.まず, 外科的遠隔疾患では, 胆石症が7例に認められたが, 60歳代以上の例ではみられないのが注目された. 症状については, 術後6カ月以上では全体に少なく年代的に著しい差はみられない. 摂食状況および就業状況についてもとくに高年者で不利とはいえないようである.術後体重の推移は, ほとんどの症例で術後5年以上経過すると安定しているが, 若年者ほど良好な経過を示し, 術前すでに標準体重±5.0kgの範囲より低下している高年者では, 体重の改善は期待できないようである. 血色素量の変動も術後5年以上で安定する例が多いが, 高年者群では低血色素状態の出現率が高い. 血清蛋白の推移は, 各年代とも良好で年代による差はほとんどみられず, 肝機能障害による影響が大きいと考えられる.したがって, 60歳代以上の高年者群に対しては体重, 血色素量の経過に注意し, とくに長期にわたる定期的健康管理が必要であると思われる. more...

A mixed intestinal adenocarcinoma-argentaffin carcinoma of the vagina in a 32-year-old woman is reported. Special stains showed the argentaffin and argyrophil reactions of the small cell population of this tumor. The small cells also contained serotonin as demonstrated by immunocytochemistry. Electron microscopy revealed characteristic cytoplasmic neurosecretory granules. The large cells were columnar and contained mucin droplets similar to those in Goblet cells in the intestines. The observations suggest that the tumor was mixed intestinal adenocarcinoma-argentaffin carcinoma (malignant carcinoid), which probably arose in aberrant intestinal epithelial cells in the vagina. The patient died with metastases of pure argentaffin carcinoma in 1 year. more...

A case of peritoneal melanosis secondary to a ruptured benign cystic teratoma in a 28-year-old woman is reported. The patient had no history of cutaneous or ocular malignant melanotic lesions. The section of the left ovary contained benign teratoid elements. The ultrastructure of the omental and peritoneal pigmented nodules confirmed that the lesions consisted of histiocytes phagocytizing massive melanin pigments. Although no melanocytic neoplasm was found in the ovarian cystic teratoma, circumstance suggests that the ovarian, omental, and peritoneal pigmented lesions were secondary reactions to melanin released from the ruptured cystic teratoma. more...

Nippon Synthetic Chemical Industry Co., Ltd. has developed a new form of binder, identified as a Gohsenol p-200, specifically designed for vinylon fibers.The effects of PVA powder as a bonding agent of vinylon paper have been mentioned in practice. The manufacture of vinylon paper on a pilot fourdrinier paper machine by using PVA powder as a bonding agent by the beater addition were studied.Physico-chemical properties of vinylon paper by using PVA powder is better than that of PVA fiber.PVA powder is convenient to handle and paper-making readily in the mill. For the most efficient results, care should be taken to select the preferred PVA powder for the specific need. more...

The results of a study of the properties of paper treated with PVA powder by the beater addition are presented.Factors affecting the retention and the strength of the sheets are discussed including the rate of dissolution, particle size of the resin in the range of saponification degree 95.7-99.9%. The absorption water of the sheets are needed more than 60% before drying process.Major advantage was found in the use of PVA powder as beater addition for paper strength. more...

Granulosa cells were obtained from human ovarian follicles. In cultured granulosa cells obtained from large follicles clear-cut ultrastructural features of steroid secreting cells were not observed due to the paucity of smooth endoplasmic reticulum. This is in keeping with their low progesterone secretion rate as measured by the RIA method and seems to indicate an early stage of luteinization. In cultured granulosa cells obtained from small follicles, oil-red-O-stained lipid droplets were observed mostly in stromal cell layers, while in large follicles under light microscopy these were located in the granulosa cell layers. These lipid droplets may play an important role in progesterone production, but the amount of lipid clearly does not always reflect active hormone secretion, since the above results indicated low progesterone secretion. Numerous intracellular microfilaments were seen under electron microscopy in cultured granulosa cells obtained from large follicles over a 3-day period. During this same time, progesterone production increased, and then decreased gradually. The microfilaments in granulosa cells may, therefore, be related to progesterone production. more...

Immunologic evaluations of women with genital neoplasia-papilloma syndrome demonstrated the presence of subclinical immunodeficiency when compared with results in 20 control women. All patients with genital neoplasia-papilloma syndrome were previously found to have human papillomavirus deoxyribonucleic acid in genital neoplasias or papillomas occurring either synchronously (in at least two genital organs at the same time) or metachronously (at different times during a period of months to years). Immunologic tests included blastogenic responses of lymphocytes to mitogens (phytohemagglutinin, concanavalin A, pokeweed mitogen, and tetanus antigen) and lymphocyte phenotyping with the use of monoclonal antibodies (OKT3, OKT4, OKT8, and OKT11). As compared with those of control subjects, the responses of the lymphocytes of patients with genital neoplasia-papilloma syndrome to mitogens were significantly decreased. The group with genital neoplasia-papilloma syndrome had a significantly higher percentage of suppressor-cytotoxic T cells (OKT8-positive cells) when compared with that of control subjects (mean 33% versus 18%) and a lower proportion of helper T cells (OKT4-positive cells) when compared with that of control subjects (35% versus 50%). The mean helper-to-suppressor/cytotoxic T-cell ratio (mean OKT4/OKT8 ratio) in the human papillomavirus-infected women was 1.72 +/- 0.29 (SE) as compared with 3.21 +/- 0.33 (SE) in the control group, demonstrating a significant reduction of the ratio in the patients with genital neoplasia-papilloma syndrome. These findings suggest that patients with genital neoplasia-papilloma syndrome have a reduced suppressor/cytotoxic T-cell ratio (mean OKT4/OKT8 ratio; that in the human papillomavirus-infected women was 1.72 +/- 0.29 (SE) as compared with 3.21 +/- 0.33 (SE) in the control group, demonstrating a significant reduction of the ratio in patients with genital neoplasia-papilloma syndrome. These findings suggest that patients with genital neoplasia-papilloma syndrome have reduced immunocompetence of unknown etiology. more...

The spectrum of vulvar intraepithelial neoplasia (VIN) was investigated with human papillomavirus (HPV) DNA probes by Southern blot hybridization technique. The results of vulvar tissue examinations from 25 patients were compared to prior genital and systemic diseases, clinical presentation, and histopathologic manifestations. The presence of HPV DNA in these lesions was largely associated with multifocality of the lesions, the presence of synchronous and metachronous multicentric genital neoplasia, and depressed immunocompetence. These findings indicate that VIN is associated with HPV and may have an infectious etiology. more...