[Effect of sacubitril/valsartan on cardiac function in heart failure rabbits with preserved ejection fraction]

Objective: To investigate the effect of sacubitril/valsartan on cardiac function in heart failure rabbits with preserved ejection fraction. Methods: Forty-five healthy adult male New Zealand rabbits were divided into sham operation group (n=12) and model group (n=33) by random number table method. HFpEF model was constructed by abdominal aortic constriction in model group. In sham operation group, 1 rabbit died due to anesthesia accident, and 1 rabbit in model group died of acute left heart failure. At 8 weeks of modeling, 3 rabbits were excluded due to the failure to establish the successful model. At the 8th week of modeling, 2 rabbits in sham operation group were selected and sacrificed by random number table method, and 3 rabbits in model group were selected and sacrificed for myocardial histological examination. Then, 9 rabbits in sham operation group and 26 rabbits in model group entered the subsequent experiment. The model group was randomly divided into untreated group (n=8), valsartan intervention group (n=9), and sacubitril/valsartan intervention group (n=9), respectively, drugs were applied per gavage. The feeding and exercise activity of rabbits in each group were evaluated by simple cardiac function classification at baseline, 4 and 8 weeks post intervention. Echocardiography was used to detect interventricular septal thickness at diastole(IVSd), interventricular septal thickness at systolic(IVSs), left ventricular posterior wall of diastolic(LVPWd), left ventricular internal diameter at diastolic(LVIDd), left ventricular internal diameter at systolic(LVIDs), and calculate the left ventricular ejection fraction(LVEF), mitral valve's early diastolic flow velocity(E)/late mitral diastolic maximum flow rate ratio(A) and heart rate at baseline, 4 and 8 weeks post intervention. Serum N terminal B-type natriuretic peptide (NT-proBNP) and angiotensin (Ang)Ⅱ and soluble matrix lysin 2(sST2) content was determined by ELISA at baseline, 4 and 8 weeks post intervention. Eight weeks after intervention, the hearts of rabbits were taken and weighed, and heart mass index (HMI) and left ventricular mass index (LVMI) were calculated. Results: (1) Evaluation results of cardiac function: there were 2, 5, and 2 rabbits with cardiac function grade Ⅰ,Ⅱ and Ⅲ before the drug intervention, and 4, 4, and 1 rabbits with respective cardiac function grade after 8 weeks of intervention in valsartan group (P>0.05). There were 2, 4, and 3 rabbits with heart function gradeⅠ,Ⅱ and Ⅲ before the drug intervention, and 7, 2, and 0 rabbits with respective heart function grade after 8 weeks of intervention in sacubitril/valsartan group(P<0.05). (2) Echocardiographic results: at 8 weeks after drug intervention, IVSd and IVSs of rabbits in untreated group were significantly higher than those in sham operation group, and the ratio of E/A was significantly lower than that in sham operation group(all P<0.01). IVSs of the valsartan group was significantly higher than that of sham operation group, and the ratio of E/A was significantly lower than that of sham operation group(all P<0.01). The E/A ratio in the sacubitril/valsartan group was significantly lower than that in sham operation group(P<0.01). IVSd and IVSs in valsartan group were significantly lower than those in untreated group(all P<0.05), and IVSd in sacubitril/valsartan group was significantly lower than that in untreated group(P<0.01). The IVSd, IVSs, LVPWd, LVIDd, LVIDs, LVEF, E/A ratios were similar between sacubitril/valsartan group and valsartan group(all P>0.05). There was no significant difference in heart rate between the groups(P>0.05). (3) Serum NT-proBNP, Ang Ⅱ and sST2 levels: 4 weeks after drug intervention, untreated group, valsartan group, and sacubitril/valsartan group's serum NT-proBNP levels were significantly higher than that of sham operation group(all P<0.01); serum NT-proBNP was significantly lower in sacubitril/valsartan group than that in untreated group(P<0.01). Four weeks after intervention, serum AngⅡ levels were significantly higher in untreated group, valsartan group, sacubitril/valsartan group than in sham group(all P<0.01), but there was no statistically significant difference between the modeling groups(P>0.05). Four weeks after drug intervention, the serum sST2 contents in untreated group, valsartan group, and sacubitril/valsartan group were significantly higher than in sham operation group(all P<0.01), and which was significantly lower in valsartan group and sacubitril/valsartan group than in untreated group(all P<0.01), which were significantly lower in sacubitril/valsartan group than in valsartan group(P<0.01). Eight weeks after drug intervention, serum NT-proBNP levels were significantly higher in untreated group, valsartan group, and sacubitril/valsartan group than in sham operation group(all P<0.01), which were significantly lower in valsartan group and sacubitril/valsartan group than in untreated group(all P<0.01), which were significantly lower in valsartan group than in sacubitril/valsartan group(P<0.01). Eight weeks after drug intervention, Ang Ⅱ levels were significantly higher in valsartan group and sacubitril/valsartan group than in untreated group(all P<0.01), which tended to be higher in untreated group and valsartan group, tended to be lower in sacubitril/valsartan compared to value at 4 weeks(all P>0.05). Eight weeks after drug intervention, serum sST2 was significantly higher in untreated group and valsartan group than in sham operation group(all P<0.01), which tended to be higher in sacubitril/valsartan group compared to sham operation group(P>0.05), which were significantly lower in valsartan group and sacubitril/valsartan group than in untreated group(all P<0.01), which was significantly lower in sacubitril/valsartan group than in valsartan group(P<0.01). (4) Comparison of whole-heart mass, left ventricular mass, HMI and LVMI: 8 weeks after drug intervention, the whole-heart mass, left ventricular mass, HMI and LVMI were significantly higher in untreated group than in sham operation group(all P<0.01), and the above indexes were also significantly higher in valsartan group than in sham operation group(all P<0.05), tended to be lower in valsartan group compared to untreated group (all P>0.05). HMI and LVMI were lower in sacubitril/valsartan group than in untreated group(all P<0.05). All the above indexes tended to be lower in sacubitril/valsartan group than in valsartan group(all P>0.05). Conclusion: Sacubitril/valsartan is superior to valsartan alone on improving cardiac function in HFpEF rabbits.

In situ X-ray absorption fine structure study on the polymerization of isoprene assisted by Nd-based ternary catalysts

Polymerization processes of isoprene catalyzed by four catalysts with different alkylaluminums were detected by in situ XAFS technique. The catalytic mechanism of the neodymium-based ternary catalyst was discussed based on the structure information.

Association between personal basic information, sleep quality, mental disorders and erectile function: a cross-sectional study among 334 Chinese outpatients

Male erectile dysfunction (ED) may cause anxiety and depression, while mental disorders and sleep disturbances may also be closely related to ED. However, the exact nature of their relationship remains unclear, and whether personal basic background data affect erectile function is unknown. We conducted a cross-sectional study among Chinese outpatients with ED from January 2012 to December 2014. All the men answered a questionnaire collecting information about mental health status, sleep disturbances and personal data, underwent a physical examination and had a blood sample drawn. Sleep disturbances were assessed on the basis of a 19-item version of the Pittsburgh Sleep Quality Index, which includes questions on sleep patterns during the past month. Among the 462 patients, 128 patients with alcohol abuse, diabetes, hypertension, hyperlipidaemia, psychiatric drugs, neurologic injury or abnormal hormones were excluded from the study; 86.27% and 68.66% of the patients suffered from anxiety and depression respectively. Sleep quality and anxiety symptoms significantly affected erectile function, whereas personal income and education level had no significant effects. Our study suggested that it is necessary to pay attention to the psychological status of patients with ED, especially anxiety disorder. Sleep quality may be an important factor affecting erectile function according to the personal data.

Viral contribution to dissolved DNA in the marine environment as determined by differential centrifugation and kingdom probing

Dissolved or filterable (<0.2-(mu)m-pore-size filter) DNA is a ubiquitous component of the dissolved organic matter in the surface waters of this planet. In an effort to understand the composition and possible sources, we subjected dissolved DNA concentrated by vortex flow filtration from offshore and coastal environments to differential centrifugation and probing with 16S rRNA-targeted kingdom oligonucleotide probes. Initial studies with calf thymus soluble DNA and T2 phage particles indicated that high-speed ultracentrifugation (201,000 x g for 90 min), a method to separate viral particles from soluble DNA used by other investigators, resulted in pelleting of nearly all the DNA and virus particles. Lower-speed centrifugation (11,200 to 25,800 x g for 90 min) resulted in >99% of the virus particles being collected in the pellet and (equiv)65% of the calf thymus DNA remaining in the supernatant. Employing this approach, we estimate that approximately 50% of the filterable DNA from marine environments is truly soluble or free DNA and that the other half is composed of bound forms (viral particles and, potentially, colloids). Of the bound form, 17 to 30% could be accounted for by viral particles, by calculating the amount of viral DNA on the basis of viral abundance, leaving a portion of the bound form uncharacterized. Kingdom probing with universal, eubacterial, and eucaryotic probes indicated that dissolved DNA hybridized with all of these probes, while purified standard viral DNAs did not, or hybridized only slightly with the universal probe (tailed oligonucleotide only). Collectively, these data indicate that DNA in viral particles is a small component of the dissolved DNA, the majority being of eubacterial and eucaryotic origin.

Ecology of coliphages in southern California coastal waters

AIMS

This study aims to investigate the ecology of coliphages, an important microbial pollution indicator. Specifically, our experiments address (i) the ability of environmental Escherichia coli (E. coli) to serve as hosts for coliphage replication, and (ii) the temporal and spatial distribution of coliphages in coastal waters.

METHODS AND RESULTS

Water samples from three locations in California's Newport Bay watershed were tested for the presence of coliphages every 2 weeks for an entire year. A total of nine E. coli strains isolated from various sources served as hosts for coliphage detection. Coliphage occurrence was significantly different between freshwater, estuarine and coastal locations and correlated with water temperature, salinity and rainfall in the watershed. The coliphages isolated on the environmental hosts had a broad host-range relative to the coliphages isolated on an E. coli strain from sewage and a US EPA recommended strain for coliphage detection.

CONCLUSIONS

Coliphage occurrence was related to the temperature, rainfall and salinity within the bay. The adaptation to a broad host-range may enable the proliferation of coliphages in the aquatic environment.

SIGNIFICANCE AND IMPACT OF THE STUDY

Understanding the seasonal variation of phages is useful for establishing a background level of coliphage presence in coastal waters. The broad host-range of coliphages isolated on the environmental E. coli host calls for investigation of coliphage replication in the aquatic environment.

Dynamic modeling of photothermal interactions for laser-induced interstitial thermotherapy: parameter sensitivity analysis

A two-dimensional model was developed to model the effects of dynamic changes in the physical properties on tissue temperature and damage to simulate laser-induced interstitial thermotherapy (LITT) treatment procedures with temperature monitoring. A modified Monte Carlo method was used to simulate photon transport in the tissue in the non-uniform optical property field with the finite volume method used to solve the Pennes bioheat equation to calculate the temperature distribution and the Arrhenius equation used to predict the thermal damage extent. The laser light transport and the heat transfer as well as the damage accumulation were calculated iteratively at each time step. The influences of different laser sources, different applicator sizes, and different irradiation modes on the final damage volume were analyzed to optimize the LITT treatment. The numerical results showed that damage volume was the smallest for the 1,064-nm laser, with much larger, similar damage volumes for the 980- and 850-nm lasers at normal blood perfusion rates. The damage volume was the largest for the 1,064-nm laser with significantly smaller, similar damage volumes for the 980- and 850-nm lasers with temporally interrupted blood perfusion. The numerical results also showed that the variations in applicator sizes, laser powers, heating durations and temperature monitoring ranges significantly affected the shapes and sizes of the thermal damage zones. The shapes and sizes of the thermal damage zones can be optimized by selecting different applicator sizes, laser powers, heating duration times, temperature monitoring ranges, etc.

Effects of dynamic changes of tissue properties during laser-induced interstitial thermotherapy (LITT)

A two-dimensional model including the effects of dynamic changes in the physical properties on tissue temperature and damage was developed to describe laser energy transport, heat transfer, and damage accumulation during laser-induced interstitial thermotherapy (LITT). The Monte Carlo method was used to simulate photon transport in a tissue in the nonuniform optical property field, with the finite difference method used to solve the Pennes bioheat equation to calculate the temperature distribution and the Arrhenius equation used to predict the extent of thermal damage. The numerical results showed that the dynamic changes in the optical properties, thermal properties, and blood perfusion rate significantly affected damage volume accumulation and temperature history and should be included in numerical simulations of the LITT treatment.

PCR detection of pathogenic viruses in southern California urban rivers

AIMS

To investigate human viral contamination in urban rivers and its impact on coastal waters of southern California, USA.

METHODS AND RESULTS

Three types of human viruses (adeno, entero and hepatitis A) were detected using nested- and RT-PCR from 11 rivers and creeks. Faecal indicator bacteria as well as somatic and F-specific coliphage were also tested. Approximately 50% of the sites were positive for human adenoviruses. However, there was no clear relationship between detection of human viruses and the concentration of indicator bacteria and coliphage. Both faecal indicator bacteria and human viral input at beaches near river mouths were associated with storm events. The first storm of the wet season seemed to have the greatest impact on the quality of coastal water than following storm events.

CONCLUSIONS

This study provides the first direct evidence that human viruses are prevalent in southern California urban rivers. Urban run-off impacts coastal water quality most significantly during the storm season.

SIGNIFICANCE AND IMPACT OF THE STUDY

To protect human health during water recreational activities, it is necessary to develop effective strategies to manage urban run-off during storm events.

Effects of thermal properties and geometrical dimensions on skin burn injuries

A one-dimensional multi-layer model is presented to characterise the skin burn process resulting from the application of a high temperature heat source to a skin surface. Transient temperatures were numerically calculated using a finite difference method to solve the Pennes bioheat equation. A damage function denoting the extent of burn injury was then calculated using the Arrhenius assumptions. The model was used to predict the effects of thermal physical properties and geometrical dimensions on the transient temperature and damage function distributions. The results show that the epidermis and dermis thicknesses significantly affect the temperature and burn injury distributions, while variations of the initial temperatures and the blood perfusion have little effect.

Giant cell reparative granuloma of the temporal bone

Giant cell reparative granuloma (GCRG) is an uncommon non-neoplastic lesion that typically occurs in the mandible and maxilla: however, its involvement with the temporal bone is rare. It is usually misdiagnosed as a giant cell tumor. Although regarded as a benign process, GCRG may be locally aggressive. In this paper, we describe two cases of GCRG of the temporal bone and review the pertinent literature published in English. The clinical course, histological evaluation, diagnosis, differential diagnosis, treatment and prognosis of GCRG of the temporal bone were investigated.

[Culture of human nasal respiratory epithelial cells in serum free medium supplemented with hormones and growth factors and measurement of human nasal ciliary motility using videomicroscopy]

OBJECTIVE

To establish a culture model of human nasal respiratory epithelial cells and a method of measuring human nasal ciliary motility.

METHOD

The human nasal respiratory epithelial cells were detached with collagenase and cultured in serum free medium supplemented with hormones and growth factors, the ciliary beat frequency was measured by videomicroscopy.

RESULT

After inoculation, cells cultured with this method adhered in 24 hours, confluented in 6-8 days and lived for 16 days. During that time ciliary beating was active, both acidic and neutral mucoitin granules were rich in goblet cells and all chromosome of 23 pairs were normal, the ciliary beat frequency in 29 subjects' nasal mucosa was (411 +/- 24) beats/min (mean +/- s).

CONCLUSION

A culture model of human nasal respiratory epithelial cells in serum free medium supplemented with hormones and growth factors and a method of measuring human nasal ciliary motility was successfully established.

Genetic diversity of Vibrio cholerae in Chesapeake Bay determined by amplified fragment length polymorphism fingerprinting

Vibrio cholerae is indigenous to the aquatic environment, and serotype non-O1 strains are readily isolated from coastal waters. However, in comparison with intensive studies of the O1 group, relatively little effort has been made to analyze the population structure and molecular evolution of non-O1 V. cholerae. In this study, high-resolution genomic DNA fingerprinting, amplified fragment length polymorphism (AFLP), was used to characterize the temporal and spatial genetic diversity of 67 V. cholerae strains isolated from Chesapeake Bay during April through July 1998, at four different sampling sites. Isolation of V. cholerae during the winter months (January through March) was unsuccessful, as observed in earlier studies (J. H. L. Kaper, R. R. Colwell, and S. W. Joseph, Appl. Environ. Microbiol. 37:91-103, 1979). AFLP fingerprints subjected to similarity analysis yielded a grouping of isolates into three large clusters, reflecting time of the year when the strains were isolated. April and May isolates were closely related, while July isolates were genetically diverse and did not cluster with the isolates obtained earlier in the year. The results suggest that the population structure of V. cholerae undergoes a shift in genotype that is linked to changes in environmental conditions. From January to July, the water temperature increased from 3 degrees C to 27.5 degrees C, bacterial direct counts increased nearly an order of magnitude, and the chlorophyll a concentration tripled (or even quadrupled at some sites). No correlation was observed between genetic similarity among isolates and geographical source of isolation, since isolates found at a single sampling site were genetically diverse and genetically identical isolates were found at several of the sampling sites. Thus, V. cholerae populations may be transported by surface currents throughout the entire Bay, or, more likely, similar environmental conditions may be selected for a specific genotype. The dynamic nature of the population structure of this bacterial species in Chesapeake Bay provides new insight into the ecology and molecular evolution of V. cholerae in the natural environment.

Genetic diversity of clinical and environmental isolates of Vibrio cholerae determined by amplified fragment length polymorphism fingerprinting

Vibrio cholerae, the causative agent of major epidemics of diarrheal disease in Bangladesh, South America, Southeastern Asia, and Africa, was isolated from clinical samples and from aquatic environments during and between epidemics over the past 20 years. To determine the evolutionary relationships and molecular diversity of these strains, in order to understand sources, origin, and epidemiology, a novel DNA fingerprinting technique, amplified fragment length polymorphism (AFLP), was employed. Two sets of restriction enzyme-primer combinations were tested for fingerprinting of V. cholerae serogroup O1, O139, and non-O1, O139 isolates. Amplification of HindIII- and TaqI-digested genomic DNA produced 30 to 50 bands for each strain. However, this combination, although capable of separating environmental isolates of O1 and non-O1 strains, was unable to distinguish between O1 and O139 clinical strains. This result confirmed that clinical O1 and O139 strains are genetically closely related. On the other hand, AFLP analyses of restriction enzyme ApaI- and TaqI-digested genomic DNA yielded 20 to 30 bands for each strain, but were able to separate O1 from O139 strains. Of the 74 strains examined with the latter combination, 26 serogroup O1 strains showed identical banding patterns and were represented by the O1 El Tor strain of the seventh pandemic. A second group, represented by O139 Bengal, included 12 strains of O139 clinical isolates, with 7 from Thailand, 3 from Bangladesh, and 2 from India. Interestingly, an O1 clinical isolate from Africa also grouped with the O139 clinical isolates. Eight clinical O1 isolates from Mexico grouped separately from the O1 El Tor of the seventh pandemic, suggesting an independent origin of these isolates. Identical fingerprints were observed between an O1 environmental isolate from a river in Chile and an O1 clinical strain from Kenya, both isolated more than 10 years apart. Both strains were distinct from the O1 seventh pandemic strain. Two O139 clinical isolates from Africa clustered with environmental non-O1 isolates, independent of other O139 strains included in the study. These results suggest that although a single clone of pathogenic V. cholerae appears responsible for many cases of cholera in Asia, Africa, and Latin America during the seventh pandemic, other cases of clinical cholera were caused by toxigenic V. cholerae strains that appear to have been derived locally from environmental O1 or non-O1 strains.

Intense noise-induced apoptosis in hair cells of guinea pig cochleae

Cells can die by two distinct pathways: apoptosis and necrosis. To explore whether intense noise can induce hair cell (HC) death via the apoptotic pathway, we systematically examined morphological changes in guinea pig cochlear HC nuclei stained with Hoechst 33342, a fluorescent dye specifically labelling the nuclear DNA. A narrow band noise centred at 4 kHz with levels at 110 dB, 115 dB or 120 dB (SPL) was applied for 4 h and the exposed cochleae were collected at various intervals (3 h, 3 or 14 days) after the noise exposure. Auditory function was monitored by measuring thresholds of auditory brain stem responses. In the noise-damaged cochleae, there were two major types of nuclear changes, nuclear condensation appeared as karyorrhexis or karyopyknosis and nuclear swelling. Karyorrhexis and karyopyknosis predominately appeared in the severely damaged cochlear region in the animals exposed to 120 dB noise and examined 3 h after the noise exposure. In contrast, swelling of nuclei occurred in all of the noise-exposed cochleae, and was the feature change in the animals exposed to 110 and 115 dB noise. This pathological change persisted at least for 14 days after the noise exposure. The typical changes of karyorrhexis and karyopyknosis noted in the animals exposed to 120 dB noise were morphologically similar to those nuclear changes described in previous studies for apoptosis, suggesting that the apoptotic process may be involved in intense noise-induced HC death.

[Computed tomographic findings of the development of the bone around the vestibular aqueduct in Meniere's disease]

OBJECTIVE

To study the development of the bone around the vestibular aqueduct (VA) in Meniere's disease (MD) by CT.

METHOD

The experiment consisted of three groups; normal ear group, non-MD vertigo group and MD group. VA in each group was examined by CT, and the minimum distance between the posterior semicircular canal and the posterior petrous surface where contain the endolymphatic sac.

RESULT

VA visualization rate in MD was low, P-P distance in MD group was shorter than that of normal ear group and non-MD vertigo group.

CONCLUSION

It is the fundamental pathological anatomy in MD that VA and the bone around VA are maldeveloped.

[Monitoring calcium in outer hair cells with confocal microscopy and fluorescence ratios of fluo-3 and fura-red]

Calcium distribution and mobilization during mechanical stimulation in outer hair cells of the guinea pig were monitored using laser scanning confocal microscopy and co-loaded fluo-3 and fura-red fluorescent probes. Spatial calcium gradients were revealed among various subcellular areas. The ratios of the fluorescence intensity of fluo-3 and fura-red were 1.71 +/- 0.85, 1.61 +/- 0.75, 1.47 +/- 0.65 and 1.39 +/- 0.66 for the cytoplasm, the cytoplasmic membrane, the cuticular plate and the nucleus respectively, indicating that free calcium ion concentrations are the highest in the cytoplasm and the lowest in the nucleus. While the calcium concentration remained relatively constant under resting conditions, it increased during mechanical stimulation. The results show that confocal ratio imaging of fluo-3 and fura-red enables us to determine more accurately the subcellular calcium distribution and that the calcium ions make a contribution to the mechanic-electrical transduction in hair cells.

Gene transfer by transduction in the marine environment

To determine the potential for bacteriophage-mediated gene transfer in the marine environment, we established transduction systems by using marine phage host isolates. Plasmid pQSR50, which contains transposon Tn5 and encodes kanamycin and streptomycin resistance, was used in plasmid transduction assays. Both marine bacterial isolates and concentrated natural bacterial communities were used as recipients in transduction studies. Transductants were detected by a gene probe complementary to the neomycin phosphotransferase (nptII) gene in Tn5. The transduction frequencies ranged from 1.33 x 10(-7) to 5.13 x 10(-9) transductants/PFU in studies performed with the bacterial isolates. With the mixed bacterial communities, putative transductants were detected in two of the six experiments performed. These putative transductants were confirmed and separated from indigenous antibiotic-resistant bacteria by colony hybridization probed with the nptII probe and by PCR amplification performed with two sets of primers specific for pQSR50. The frequencies of plasmid transduction in the mixed bacterial communities ranged from 1.58 x 10(-8) to 3.7 x 10(-8) transductants/PFU. Estimates of the transduction rate obtained by using a numerical model suggested that up to 1.3 x 10(14) transduction events per year could occur in the Tampa Bay Estuary. The results of this study suggest that transduction could be an important mechanism for horizontal gene transfer in the marine environment.

Characterization of marine temperate phage-host systems isolated from Mamala Bay, Oahu, Hawaii

To understand the ecological and genetic role of viruses in the marine environment, it is critical to know the infectivity of viruses and the types of interactions that occur between marine viruses and their hosts. We isolated four marine phages from turbid plaques by using four indigenous bacterial hosts obtained from concentrated water samples from Mamala Bay, Oahu, Hawaii. Two of the rod-shaped bacterial hosts were identified as Sphingomonas paucimobilis and Flavobacterium sp. All of the phage isolates were tailed phages and contained double-stranded DNA. Two of the phage isolates had morphologies typical of the family Siphoviridae, while the other two belonged to the families Myoviridae and Podoviridae. The head diameters of these viruses ranged from 47 to 70.7 nm, and the tail lengths ranged from 12 to 146 nm. The burst sizes ranged from 7.8 to 240 phage/bacterial cell, and the genome sizes, as determined by restriction digestion, ranged from 36 to 112 kb. The members of the Siphoviridae, T-phi HSIC, and T-phi D0, and the member of the Myoviridae, T-phi D1B, were found to form lysogenic associations with their bacterial hosts, which were isolated from the same water samples. Hybridization of phage T-phi HSIC probe with lysogenic host genomic DNA was observed in dot blot hybridization experiments, indicating that prophage T-phi HSIC was integrated within the host genome. These phage-host systems are available for use in studies of marine lysogeny and transduction.

Coliphage and indigenous phage in Mamala Bay, Oahu, Hawaii

Public concern over the discharge of primarily treated sewage by two offshore outfalls in Mamala Bay, Oahu, prompted a multidisciplinary study to determine the impact of such activities on the water quality in the bay and at adjacent recreational beaches. As part of this study, we determined the abundance of coliphage as an indicator of fecal pollution along with total viral direct counts and phages infective for Vibrio parahaemoltyicus 16 at stations in Mamala Bay in four quarterly samplings over 13 months. Coliphage (< 1 to 1.2 x 10(3)/liter) were found during each quarterly sampling along an offshore transect to the Sand Island waste treatment facility outfall. The nonpoint coastal stations (Pearl Harbor, Ala Wai Canal, and Ke'ehi Lagoon) had high levels of coliphage during the storm event sampling in February 1994 but much lower levels or none when sampled during dry weather. Coliphage were absent at all samplings at Waikiki Beach and at the control station off Diamond Head. Viral direct counts in eutrophic coastal stations (Pearl Harbor, Ke'ehi Lagoon, Ala Moana Beach, and Ala Wai canal) averaged 10(9)/liter, while counts at offshore stations ranged from 9 x 10(7) to 1 x 10(9) viruses/liter, values similar to those for other marine environments. Vibriophage were found mainly in eutrophic coastal environments (Ala Wai Canal, Pearl Harbor, and Ke'ehi Lagoon) and at the Sand Island Transect stations D1 and D2. The greatest abundance was found during the storm event (February 1994) sampling. These results suggest that the Sand Island outfall influenced the water quality of the immediate surrounding waters but had little effect on the quality of the recreational beaches. Nonpoint discharge sources appeared to be more important in the distribution of fecal indicators in the coastal zone.

The embryonic development of the human ethmoid labyrinth from 8-40 weeks

The embryonic development of the human ethmoid labyrinth was studied in 24 fetal heads aged between 8 and 40 weeks of gestation under light microscopy. The uncinate process was identifiable at 8 weeks of gestation on the laterosuperior portion of the inferior turbinate; however, at this stage of development, the ethmoid bulla was not apparent. The ethmoid bulla developed on the lateral wall of the middle meatus by 12 weeks of gestation. By 14 weeks, the primordial ethmoid infundibulum and primordial maxillary sinus were seen developing between the uncinate process and the ethmoid bulla. It was obvious that the anterior and middle ethmoid cells developed from the ethmoid bulla. By 22 weeks of gestation, the first cell of the anterior ethmoid group was evident in the anterior-inferior portion of the ethmoid bulla. By 23 weeks of gestation, the first cell of the middle ethmoid group was visible in the superior portion of the ethmoid bulla. Pneumatization of the middle turbinate occurred as part of normal development of the ethmoid labyrinth. By 32 weeks of gestation, the ostium for the development of the middle turbinate cell was seen in the superior-interior portion of the middle turbinate. These observations provide new insight into the development of the ethmoid labyrinth and have important implications for the understanding of normal anatomy and developmental variants of the ethmoid labyrinth.

The role and significance of chondroitin sulfate in the development of otosclerosis

Chondroitin sulfate is a sulfated glycosaminoglycan that predominates in the ground substance of cartilage. Using monoclonal antichondroitin sulfate in 61 specimens of human otosclerotic lesions, we studied the distribution of this glucosaminoglycan in various stages of otosclerosis. Our findings show that chondroitin sulfate plays an important role in the development of otosclerosis. In addition, the distribution of chondroitin sulfate clearly delineates the stage of otosclerosis referred to as active into two distinct histologic stages. Dividing the active stage into "osteolytic" and "sponge-chondroid" would be reasonable based on our findings.

Effect of focal cochlear vascular lesion on endocochlear potential in guinea pigs

The alteration endocochlear potential (EP) in response to total cochlear ischemia induced by various experimental manipulations has been studied. However, the effect of restricted areal damage to the microvessels (restricted to small area in the lateral wall of a cochlear turn) on the EP value is still unknown. In the current investigation we adopted a photochemical method to produce a focal (i.e., restricted area) microvessel injury in the lateral wall of the guinea pig cochlea and examined the effect of these insults on EP recorded in the same region. The small area of the microvessel lesion (small fenestra: approximately 0.2 x 0.4 mm2) induced by photoactivation did not yield significant EP changes, suggesting that damage to such a small area of microcirculation in the lateral wall of the cochlea has no statistically significant effects on EP values. In subjects with a large area of the microvessel lesion (large fenestra: approximately 0.2 x 0.8 mm2), a decrease in the EP value (mean +/- SEM 7.9 +/- 0.8 mV) was noted. However, the control group animals with a large fenestra but without microvessel lesion also displayed a decrease (8.6 +/- 0.8 mV) in EP. In the current study we were unable to differentiate whether the EP changes in animals with the large fenestra microvessel lesions were caused by the cochlear blood flow decrease or by the surgical preparation. However, the results of this study indicated if the EP value was affected by the large area of the microvessel lesion, the level of decrease would not be large. That is, the EP decrease was less than the EP change in the control group (mean: 8.6 mV). Considering the dependence of EP on blood flow, the data of this study suggest that compensatory mechanisms in the cochlea may maintain the EP following a focal lesion in the lateral wall of the cochlea. This study also indicates that the photochemical method provides a reliable approach to produce the animal model with the focal microvessel lesion in the lateral wall of the cochlea.

Two types of calcium channels in bullfrog saccular hair cells

Ca2+ channels were studied in cell-attached recordings from the basolateral membrane of the bullfrog saccular hair cells with the EPC-9 patch-clamp system. Pipettes contained 110 mM Ba2+ and the membrane potential was zeroed with isotonic potassium aspartate. Data acquisition and analysis were performed using E9SCREEN and M2LAB software. L-type channel was distinguished by a single-channel conductance of 26 pS, activation range between -10 and +40 mV and intense activity even at a holding potential of -40 mV. The L-type channel showed characteristic bursts of brief openings (mode 1) interrupted occasionally by longer openings (mode 2). Bay K 8644 promoted the mode 2 activity and nifedipine inhibited L-type channel activity. Another type of calcium channels, 20 pS channel, was detected by -50 to +10 mV depolarizing steps from a holding potential of -40 or -80 mV. This channel was insensitive to dihydropyridines and resembled the N-type channel.

[ACh and ATP induced calcium mobilization in outer hair cells of the guinea pig cochlea: confocal microscopy]

Effects of acetylcholine (ACh) and ATP as the candidates of efferent neurotransmitter on intracellular Ca2+ concentrations ( [Ca2+]i) of the isolated outer hair cells (OHCs) from guinea pig cochlea were studied with laser scanning confocal microscope. The OHCs were loaded with Ca2+ sensitive dye Fluo-3, whose fluorescent intensity was strongest at the basal end in resting OHC. The presence of ACh gradually increased [Ca2+]i to a higher level at the basal end of OHCs. Continuous application of ATP caused a rapid [Ca2+]i increase followed by a gradual exhaustion throughout the whole OHC. Magnitude of the increase at the apex was greater than that at the base. In OHCs whose calcium had been exhausted by ATP, ACh induced a temporary increase in [Ca2+]i. It seems likely that the ACh-induced [Ca2+]i rise is partly due to an influx of extracellular Ca2+. The bursting nature of ATP-induced [Ca2+]i rise may be a consequence of Ca2+ influx through the ATP-gated cation channels and of the mobilization of intracellular store mediated by ATP.

Significance of chondrification in the development of otosclerotic stapedial footplate

Thirty-four otosclerotic stapes of active type were investigated histologically with hematoxylin-eosin (H-E), periodic acid-Schiff-alcine blue (PAS-AB), and/or toluidine blue stain. The results show that chondrification plays an important role in the development of otosclerosis. To date, this specific histopathologic change has not been well recognized. Based on the findings of this study, it is suggested that the active type of otosclerosis be subdivided into two phases, the osteolytic phase and spongy chondroid phase.

Computer-aided three-dimensional reconstruction and measurement of bony and membranous labyrinth

We used three methods to reconstruct a same bony and membranous labyrinth by an image processing work station (IPWS). Three dimensional (3-D) models of the bony and membranous labyrinth were thus obtained. Different parts of the labyrinth were measured and the spatial relationship between the bony and membranous labyrinth was observed. Many 3-D parameters such as cochlear length, volume of different parts of the labyrinth, angles among the three semicircular canals were measured. The results of this experiment are useful in the study of the cochlear and vestibular function.

The cartilaginous nasal capsule and embryonic development of human paranasal sinuses

Embryology is of importance to the surgeon both for the study of human developmental anatomy and for the analysis of congenital conditions resulting from malformed or arrested development. The embryonic development of the nose, and especially of the paranasal sinuses, is not yet fully understood. This histologic study of 23 fetal heads aged from 8 to 40 weeks of gestation demonstrates that all four pairs of paranasal sinuses are developed from the cartilaginous nasal capsule. The outpouching of the nasal mucous membranes is only a secondary phenomenon, rather than the primary force. This observation helps to elucidate the following clinical observations: (1) the association of maxillary sinus hypoplasia with hypoplasia of the uncinate process, (2) the origin of chondrosarcoma of the maxillary bone, and (3) pneumatization of the paranasal sinuses.

[Clinical efficacy of ciprofloxacin and ofloxacin]

The clinical efficacy, antibacterial activity and adverse effects of ciprofloxacin (CPLX) and ofloxacin (OFLX) produced in our country were compared in five clinical hospital in Beijing and Guangzhou in 1992. Two groups, each consisting of 100 cases, were treated with CPLX and OFLX respectively. The total cure rate was 79% and effective rate 94% after one course of treatment. There was no difference between the two groups (P > 0.05). The positive rate of presence of pathogens was 95% in both groups, but the rate of transformation from positive to negative after one course of treatment was 95.8% (OFLX) and 87.4% (CPLX) respectively. The difference between the two groups was significant (P < 0.05). 99 and 96 strains of bacteria were detected in the CPLX and OFLX group respectively; the elimination rate was 87.9% and 95.8% (P < 0.05). Incidence of adverse effects was 12% (OFLX) and 21% (CPLX) respectively. In a word, both drugs are effective in treating bacterial infections of digestive system, urinary system and respiratory tract. They are safe and reliable. OFLX is better than CPLX in bacteria elimination and incidence of adverse effects.

Distribution of viral abundance in the reef environment of Key Largo, Florida

The distribution of viral and microbial abundance in the Key Largo, Fla., reef environment was measured. Viral abundance was measured by transmission electron microscope direct counts and plaque titer on specific bacterial hosts in water and sediment samples from Florida Bay (Blackwater Sound) and along a transect from Key Largo to the outer edge of the reef tract in Key Largo Sanctuary. Water column viral direct counts were highest in Blackwater Sound of Florida Bay (1.2 x 10(7) viruses per ml), decreased to the shelf break (1.7 x 10(6) viruses per ml), and were inversely correlated with salinity (r = -0.97). Viral direct counts in sediment samples ranged from 1.35 x 10(8) to 5.3 x 10(8)/cm(3) of sediment and averaged nearly 2 orders of magnitude greater than counts in the water column. Viral direct counts (both sediment and water column measurements) exceeded plaque titers on marine bacterial hosts (Vibrio natriegens and others) by 7 to 8 orders of magnitude. Water column viral abundance did not correlate with bacterial direct counts or chlorophyll a measurements, and sediment viral parameters did not correlate with water column microbial, viral, or salinity data. Coliphage, which are indicators of fecal pollution, were detected in two water column samples and most sediment samples, yet their concentrations were relatively low (<2 to 15/liter for water column samples, and <2 to 108/cm(3) of sediment). Our findings indicate that viruses are abundant in the Key Largo environment, particularly on the Florida Bay side of Key Largo, and that processes governing their distribution in the water column (i.e., salinity and freshwater input) are independent of those governing their distribution in the sediment environment.

Techniques for isolating hair cells from guinea pig cochlea

Isolated live hair cells are important models for studies on the electrophysiology, pathology and pharmacology of the hair cell. Using mechanical isolation method after papain treatment, 70 +/- 27 hair cells, including 0 to 4 inner hair cells, could be obtained from each cochlea of 4 guinea pigs. The criteria for a good viability of isolated cochlear hair cells were: 1) a smooth hair cell membrane; 2) hair cells not swollen; 3) the nucleus in normal position; 4) the cytoplasm in a state of translucence with a halo at the periphery (birefringence); and 5) no Brownian movement of the organelles within the cytoplasm. With short-term culturing at room temperature, approximately 90% of the isolated hair cells retained a good viability at the end of two hours. Subsequently, the hair cells gradually degenerated but still, at the end of five hours, about 40% of them appeared intact. The degeneration patterns have been carefully observed and described.

Concentration of viruses and dissolved DNA from aquatic environments by vortex flow filtration

Vortex flow filtration (VFF) was used to concentrate viruses and dissolved DNA from freshwater and seawater samples taken in Florida, the Gulf of Mexico, and the Bahamas Bank. Recoveries of T2 phage and calf thymus DNA added to artificial seawater and concentrated by VFF were 72.8 and 80%, respectively. Virus concentrations determined by transmission electron microscopy of VFF-concentrated samples ranged from 3.4 x 10(7)/ml for a eutrophic Tampa Bay sample to 2.4 x 10(5) for an oligotrophic oceanic surface sample from the southeastern Gulf of Mexico. Viruslike particles were also observed in a sample taken from a depth of 1,500 m in the subtropical North Atlantic Ocean. Filtration of samples through Nuclepore or Durapore filters (pore size, 0.2 micron) prior to VFF reduced phage counts by an average of two-thirds. Measurement of dissolved-DNA content by Hoechst 33258 fluorescence in environmental samples concentrated by VFF yielded values only ca. 35% of those obtained for samples concentrated by ethanol precipitation (the standard dissolved-DNA method). However, ethanol precipitation of VFF-concentrated extracts resulted in an increase in measurable DNA, reaching 80% of the value obtained by the standard method. These results indicate that a portion of the naturally occurring dissolved DNA is in a form inaccessible to nucleases and Hoechst stain, perhaps bound to protein or other polymeric material, and is released upon ethanol precipitation. Viral DNA contents estimated from viral counts averaged only 3.7% (range, 0.9 to 12.3%) of the total dissolved DNA for samples from freshwater, estuarine, and offshore oligotrophic environments.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical evaluation of enoxacin]

436 patients with various infections were treated with 2 kinds of enoxacin preparations, tablets in 336 cases and capsules in 100 cases. The total effective rate for tablets and capsules was 97.0% and 95.0% respectively. The bacterial eradication rate was 96.8% for tablets and 96.7% for capsules. Adverse reactions were few and mild. A randomized study of enoxacin and norfloxacin in the treatment of 209 patients with enteric and urinary infections was carried out simultaneously, the effective rate of enoxacin (99.1%) was similar to norfloxacin (95.0%). The incidence of side effects in norfloxacin group was slightly higher than that in enoxacin (P less than 0.05).

[Effect of fluoroquinolones made in China in the treatment of acute bacillary dysentery. A report of 212 cases]

212 cases of acute bacillary dysentery were treated with enoxacin and norfloxacin, another 15 cases were treated by chujunsheng. The cure rate in enoxacin group was 99.1%, in norfloxacin group 98.04% and in chujunsheng group 63.64%. The isolated pathogens were tested for susceptibility with disk diffusion and MIC determination. The results showed that both enoxacin and norfloxacin are better than gentamycin, ampicillin, chloramphenicol and trimethoprim-sulfamethoxazole. Side effects of enoxacin group and norfloxacin were noted in are 2.7% and 3.0% of the patients respectively. This study suggests that enoxacin and norfloxacin are highly effective, quite convenient for use and have few adverse reactions. They are considered to be drugs of choice for the treatment of acute bacillary dysentery.

40-Hz auditory event-related potential in normal adults

40-Hz event-related potentials (AERP) in response to 0.5-, 1-, 2- and 4-kHz tone pips were studied in 45 subjects (18 males and 27 females) in order to assess their reliability and threshold in normal adults and to study the effects of stimulus frequency and intensity on their latency and amplitude. In all subjects well-formed and reproducible 40-Hz AERP were detected, thus showing a good reliability of 40-Hz AERP to tone pips. The response was always detectable within 15 dB nHL intensity level and showed a sequence of positive (P1, P2 and P3) and negative (N1, N2 and N3) waves. It has also been observed that the latency of the first component following the acoustic stimulus decreased at increasing stimulus frequency and intensity, while the amplitude of the whole response increased upon increasing stimulus intensity. It can be suggested that the 40-Hz AERP to tone pips may represent a useful tool in assessing auditory threshold in the low-frequency range.