Small-molecule PIK-93 modulates the tumor microenvironment to improve immune checkpoint blockade response

Immune checkpoint inhibitors (ICIs) targeting PD-L1 immunotherapy are state-of-the-art treatments for advanced non-small cell lung cancer (NSCLC). However, the treatment response of certain patients with NSCLC is unsatisfactory because of an unfavorable tumor microenvironment (TME) and poor permeability of antibody-based ICIs. In this study, we aimed to discover small-molecule drugs that can modulate the TME to enhance ICI treatment efficacy in NSCLC in vitro and in vivo. We identified a PD-L1 protein-modulating small molecule, PIK-93, using a cell-based global protein stability (GPS) screening system. PIK-93 mediated PD-L1 ubiquitination by enhancing the PD-L1-Cullin-4A interaction. PIK-93 reduced PD-L1 levels on M1 macrophages and enhanced M1 antitumor cytotoxicity. Combined PIK-93 and anti-PD-L1 antibody treatment enhanced T cell activation, inhibited tumor growth, and increased tumor-infiltrating lymphocyte (TIL) recruitment in syngeneic and human peripheral blood mononuclear cell (PBMC) line-derived xenograft mouse models. PIK-93 facilitates a treatment-favorable TME when combined with anti-PD-L1 antibodies, thereby enhancing PD-1/PD-L1 blockade cancer immunotherapy.

Orbital angular momentum densities in the astigmatic transformation of Lissajous geometric laser modes

Orbital angular momentum densities in the astigmatic transformation of Lissajous geometric laser modes are originally and systematically investigated. The quantum theory of the coherent state is exploited to derive an analytical wave representation for the transformed output beams. The derived wave function is further employed to numerically analyze the propagation dependent orbital angular momentum densities. The parts of the negative and positive regions in the orbital angular momentum density are found to rapidly change in the Rayleigh range behind the transformation.

Antimetabolite pemetrexed primes a favorable tumor microenvironment for immune checkpoint blockade therapy

Background

The immune checkpoint blockade (ICB) targeting programmed cell death-1 (PD-1) and its ligand (PD-L1) has been proved beneficial for numerous types of cancers, including non-small-cell lung cancer (NSCLC). However, a significant number of patients with NSCLC still fail to respond to ICB due to unfavorable tumor microenvironment. To improve the efficacy, the immune-chemotherapy combination with pemetrexed, cis/carboplatin and pembrolizumab (anti-PD-1) has been recently approved as first-line treatment in advanced NSCLCs. While chemotherapeutic agents exert beneficial effects, the underlying antitumor mechanism(s) remains unclear.

Methods

Pemetrexed, cisplatin and other chemotherapeutic agents were tested for the potential to induce PD-L1 expression in NSCLC cells by immunoblotting and flow cytometry. The ability to prime the tumor immune microenvironment was then determined by NSCLC/T cell coculture systems and syngeneic mouse models. Subpopulations of NSCLC cells responding differently to pemetrexed were selected and subjected to RNA-sequencing analysis. The key signaling pathways were identified and validated in vitro and in vivo.

Results

Pemetrexed induced the transcriptional activation of PD-L1 (encoded by CD274) by inactivating thymidylate synthase (TS) in NSCLC cells and, in turn, activating T-lymphocytes when combined with the anti-PD-1/PD-L1 therapy. Nuclear factor κB (NF-κB) signaling was activated by intracellular reactive oxygen species (ROSs) that were elevated by pemetrexed-mediated TS inactivation. The TS−ROS−NF-κB regulatory axis actively involves in pemetrexed-induced PD-L1 upregulation, whereas when pemetrexed fails to induce PD-L1 expression in NSCLC cells, NF-κB signaling is unregulated. In syngeneic mouse models, the combinatory treatment of pemetrexed with anti-PD-L1 antibody created a more favorable tumor microenvironment for the inhibition of tumor growth.

Conclusions

Our findings reveal novel mechanisms showing that pemetrexed upregulates PD-L1 expression and primes a favorable microenvironment for ICB, which provides a mechanistic basis for the combinatory chemoimmunotherapy in NSCLC treatment.

Vorinostat combined with brigatinib overcomes acquired resistance in EGFR-C797S-mutated lung cancer

The development of a new generation of tyrosine kinase inhibitors (TKIs) has improved the treatment response in lung adenocarcinomas. However, acquired resistance often occurs due to new epidermal growth factor receptor (EGFR) mutations. In particular, the C797S mutation confers drug resistance to T790M-targeting EGFR TKIs. To address C797S resistance, a promising therapeutic avenue is combination therapy that targets both total EGFR and acquired mutations to increase drug efficacy. We showed that combining vorinostat, a histone deacetylase inhibitor (HDACi), with brigatinib, a TKI, enhanced antitumor effects in primary culture and cell lines of lung adenocarcinomas harboring EGFR L858R/T790M/C797S mutations (EGFR-3M). While EGFR phosphorylation was decreased by brigatinib, vorinostat reduced total EGFR-3M (L858R/T790M/C797S) proteins through STUB1-mediated ubiquitination and degradation. STUB1 preferably ubiquitinated other EGFR mutants and facilitated protein turnover compared to EGFR-WT. The association between EGFR and STUB1 required the functional chaperone-binding domain of STUB1 and was further enhanced by vorinostat. Finally, STUB1 levels modulated EGFR downstream functions. Low STUB1 expression was associated with significantly poorer overall survival than high STUB1 expression in patients harboring mutant EGFR. Vorinostat combined with brigatinib significantly improved EGFR-TKI sensitivity to EGFR C797S by inducing EGFR-dependent cell death and may be a promising therapy in treating C797S-resistant lung adenocarcinomas.

Monocarboxylate Transporter 4 Is a Therapeutic Target in Non-small Cell Lung Cancer with Aerobic Glycolysis Preference

Targeting metabolic reprogramming is an emerging strategy in cancer therapy. However, clinical attempts to target metabolic reprogramming have been proved to be challenging, with metabolic heterogeneity of cancer being one of many reasons that causes treatment failure. Here, we stratified non-small cell lung cancer (NSCLC) cells, mainly lung adenocarcinoma, based on their metabolic phenotypes and demonstrated that the aerobic glycolysis-preference NSCLC cell subtype was resistant to the OXPHOS-targeting inhibitors. We identified that monocarboxylate transporter 4 (MCT4), a lactate transporter, was highly expressed in the aerobic glycolysis-preference subtype with function supporting the proliferation of these cells. Glucose could induce the expression of MCT4 in these cells through a ΔNp63α and Sp1-dependent pathway. Next, we showed that knockdown of MCT4 increased intracellular lactate concentration and induced a reactive oxygen species (ROS)-dependent cellular apoptosis in the aerobic glycolysis-preference NSCLC cell subtype. By scanning a panel of monoclonal antibodies with MCT4 neutralizing activity, we further identified a MCT4 immunoglobulin M (IgM) monoclonal antibody showing capable anti-proliferation efficacy on the aerobic glycolysis-preference NSCLC cell subtype. Our findings indicate that the metabolic heterogeneity is a critical factor for NSCLC therapy and manipulating the expression or function of MCT4 can be an effective strategy in targeting the aerobic glycolysis-preference NSCLC cell subtype.

4(1H)-quinolone derivatives overcome acquired resistance to anti-microtubule agents by targeting the colchicine site of β-tubulin

Developing new therapeutic strategies to overcome drug resistance of cancer cells is an ongoing endeavor. From among 2 million chemicals, we identified ethyl 4-oxo-2-phenyl-1,4-dihydroquinoline-6-carboxylate (AS1712) as a low-toxicity inhibitor of lung cancer cell proliferation and xenograft tumor growth. We show that AS1712 is active against broad cancer cell lines and is able to bind in the colchicine-binding pocket of β-tubulin, thereby inhibiting microtubule assembly and, consequently, inducing mitotic arrest and apoptosis. Our cell-based structure-activity relationship study identified a new lead compound, RJ-LC-15-8, which had a greater anti-proliferative potency for H1975 cells than did AS1712, while maintaining a similar mechanism of action. Notably, AS1712 and RJ-LC-15-8 overcame P-glycoprotein efflux pump and β-tubulin alterations that lead to acquired resistance against microtubule-targeting drugs of cancer cells. AS1712 and RJ-LC-15-8 may be lead compounds that overcome acquired resistance to microtubule-targeting agents of cancer cells.

Effects of backpack and double pack loads on postural stability

Measurement of postural stability is crucial for identifying predictors of performance, determining the efficacy of physical training and rehabilitation techniques and evaluating and preventing injuries, particularly for heavy load carriage in hikers, mountain search and rescue personnel and soldiers. This study investigated the effect of load distribution on postural stability in an upright stance using backpack and double pack loads under conflicting or impaired somatosensory, visual and vestibular conditions. The sensory organisation tests were conducted on 20 young adults before and after a 10-min level walking exercise. Young adults' ability to use inputs from somatosensory and visual systems to maintain postural stability was significantly reduced following a 10-min walking exercise with a heavy backpack (30% of body weight), whereas no significant changes were observed for double pack carriage. Thus, the distribution of heavy loads to the front and back provides superior balance control compared with back-only loading. Practitioner summary: This study investigated the effects of heavy (30% of body weight) load distribution on postural stability after a 10-min walking exercise. Backpack carriage significantly reduced postural stability, whereas there was no significant effect under double pack loads. Distribution of heavy loads on the front-and-back is desirable for superior balance control.

Gender Differences in Energy Expenditure During Walking With Backpack and Double-Pack Loads

OBJECTIVE

To investigate gender differences in energy expenditure during walking with backpack and double-pack loads.

BACKGROUND

Studies have reported that energy expenditure during walking with double-pack loads is lower compared with backpack carriage. However, the effect of gender on energy expenditure while walking with these two load distribution systems has not been investigated.

METHOD

Thirty healthy young adults (15 female and 15 male participants) walked on a treadmill with backpack and double-pack loads weighing 30% of their body weight at a speed of 0.89 m/s for 10 min. The energy expenditure in terms of oxygen consumption (VO2) and respiratory exchange ratio (RER) were continuously monitored using a portable gas analyzer throughout each walking exercise. A mixed-design analysis of variance model was adopted to test the effects of gender, pack, and time on VO2 and RER.

RESULTS

No time effect was observed on VO2. However, significant gender, pack, and interaction effects were observed. The lowest VO2 was found in female participants under double-pack carriage. No significant gender or pack differences existed in RER. However, RER significantly and incrementally increased in time from the 4th through 6th, 8th, and 10th min.

CONCLUSION

This study revealed that heavy double-pack load carriage for healthy young female participants had significantly lower energy expenditure (normalized by the entire system weight, i.e., the participant's weight plus the weight of the pack) than that of the male participants in a 10-min walking exercise.

APPLICATION

The findings of this study indicated that healthy young female participants carried a heavy double-pack with less energy cost (normalized by the entire system weight, i.e., the participant's weight plus the weight of the pack) compared with their male counterparts during a 10-min walking exercise.

Sexual genetic and simple sequence repeat (SSR) analysis for molecular marker development on the all hermaphrodite papaya

The papaya (Carica papaya L.) is one of the most important economic tropical fruits in the world, and the hermaphrodite is the preferred type in field cultures. We analyzed the sexual ratio of offspring from the cultivar 'Taiwan Seed Station No. 7' (T7) by a self-cross and its cross with Taichung Sunrise (TS). Female progeny from the T7 self-crossing were not observed. This finding may be caused by a lethal gene that is linked to females. In this study, we selected 192 simple sequence repeats (SSRs) to analyze the polymorphism between T7 and TS. A total of 37 SSRs were identified for T7 and TS. In addition, 14 SSRs served as the molecular makers for identification of T7, TS and their hybrid offsprings. Thus, the results show that the genetic similarity between T7 and TS is rather high. This suggests that T7 may be a mutant of TS. Phylogenetic analysis from the SSR polymorphisms of the above parent strains and 15 F1 offspring revealed the genetic distance of the F1 offspring located between T7 and TS. The results of this study may provide an opportunity for elucidating the genetic characteristics of all hermaphrodites via identification of molecular makers.

The role of small intestinal bacterial overgrowth in postgastrectomy patients

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) is expected in postgastrectomy patients; however, its role has not been clarified. This study was to estimate the prevalence of SIBO and investigate the clinical role of SIBO in postgastrectomy patients.

METHODS

This prospective study involved 76 patients who underwent gastrectomy for early gastric cancer with no evidence of recurrence. An H(2)-CH(4) breath test with oral glucose challenge test was performed to diagnose SIBO and dumping syndrome. Sigstad dumping questionnaires, serum glucose, hematocrit and pulse rate were simultaneously monitored for every 30 min for 3 hours.

KEY RESULTS

There were significant differences in SIBO between the postgastrectomy patients and controls (77.6%vs 6.7%, P < 0.01). Abdominal fullness or borborygmus during oral glucose load were more common in SIBO-positive than in negative patients (50.8%vs 17.6%, P = 0.03), and were the independent factors for predicting SIBO in postgastrectomy patients (P = 0.02). The prevalences of dumping syndrome and hypoglycemia after oral glucose were 35 (46.1%) and 19 (25.0%), and were not different between both groups. However, the plasma glucose was significantly lower in SIBO-positive than in SIBO-negative patients at 120 and 150 min after oral glucose load (P < 0.05). No significant differences were observed in pulse rate and hematocrit in both groups.

CONCLUSIONS & INFERENCES

SIBO is common among postgastrectomy patients. It appears to be associated with postprandial intestinal symptoms and might aggravate late hypoglycemia. SIBO could be a new therapeutic target for managing intestinal symptoms in postgastrectomy patients.

The role of small intestinal bacterial overgrowth in postgastrectomy patients

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) is expected in postgastrectomy patients; however, its role has not been clarified. This study was to estimate the prevalence of SIBO and investigate the clinical role of SIBO in postgastrectomy patients.

METHODS

This prospective study involved 76 patients who underwent gastrectomy for early gastric cancer with no evidence of recurrence. An H(2)-CH(4) breath test with oral glucose challenge test was performed to diagnose SIBO and dumping syndrome. Sigstad dumping questionnaires, serum glucose, hematocrit and pulse rate were simultaneously monitored for every 30 min for 3 hours.

KEY RESULTS

There were significant differences in SIBO between the postgastrectomy patients and controls (77.6%vs 6.7%, P < 0.01). Abdominal fullness or borborygmus during oral glucose load were more common in SIBO-positive than in negative patients (50.8%vs 17.6%, P = 0.03), and were the independent factors for predicting SIBO in postgastrectomy patients (P = 0.02). The prevalences of dumping syndrome and hypoglycemia after oral glucose were 35 (46.1%) and 19 (25.0%), and were not different between both groups. However, the plasma glucose was significantly lower in SIBO-positive than in SIBO-negative patients at 120 and 150 min after oral glucose load (P < 0.05). No significant differences were observed in pulse rate and hematocrit in both groups.

CONCLUSIONS & INFERENCES

SIBO is common among postgastrectomy patients. It appears to be associated with postprandial intestinal symptoms and might aggravate late hypoglycemia. SIBO could be a new therapeutic target for managing intestinal symptoms in postgastrectomy patients.

Magnetically enhanced high-specificity virus detection using bio-activated magnetic nanoparticles with antibodies as labeling markers

This study describes magnetically driven suppression of cross-reactions among molecules. First, the magnetic nanoparticles are coated with bio-probes and dispersed in liquid. The bio-probes can then bind with homologous or heterologous bio-targets. When alternating-current (ac) magnetic fields are applied, magnetic nanoparticles rotate driven by ac magnetic fields. Thus, the bio-targets bound on the surface of magnetic nanoparticles experience a centrifugal force. The centrifugal force can be manipulated by adjusting the angular frequency of the rotating magnetic nanoparticles. The angular frequency is determined by the applied ac magnetic field frequency. Since the binding force for good binding is much higher than that of poor binding, frequency manipulation is needed for the centrifugal force to be higher than the poor-binding force but lower than the good-binding force. Therefore, poor binding which contributes to cross reactions between molecules can be suppressed efficiently by control of the ac magnetic field frequency.

Unusual pox lesions found in Chinese jungle mynahs (Acridotheres cristatellus)

Pox lesions involving feathered and unfeathered skin, the oral cavity and the uropygial gland were found in Chinese jungle mynahs. Characteristic intracytoplasmic inclusions were detected in the proliferative cells of all lesions. Ultrastructurally, the virus particles consisted of a convoluted outer membrane enclosing lateral bodies and a biconcave central core, typical for poxvirus. The nucleotide sequences of the amplicon obtained with a set of primers for the 4b core protein of fowl poxvirus revealed that the mynah poxvirus was phylogenetically related to wood pigeon poxvirus. This is the first report of poxvirus infection affecting the uropygial gland.

Oral rehabilitation of a patient with scleroderma associated with systematic lupus erythematosus: a case report

This case report presents a patient who had a limited oral opening due to systematic lupus erythematosus (SLE) and describes how oral rehabilitation was achieved with a removable partial denture. Various techniques for the delivery of oral health care have been reported for patients who have limited mouth openings as a result of SLE and scleroderma. After a review of the literature, a new approach was required for this patient with SLE who had a very limited mouth opening. The retention for the removable partial denture (RPD) used the undercut in the abutment teeth and a magnet-retained sectional RPD. A set of tweezers was modified to help with the insertion and removal of the sectional RPD by the patient. This paper reports a new clinical and laboratory technique of fabricating a sectional RPD using magnets and customized tweezers for this patient.

Development of Taenia saginata asiatica metacestodes in SCID mice and its infectivity in human and alternative definitive hosts

Development of Taenia saginata asiatica metacestodes in SCID mice, and its infectivity in humans, golden hamsters, and Mongolian gerbils as alternative definitive hosts, were investigated. Cysticerci were recovered from SCID mice that were subcutaneously injected with hatched oncospheres of T. s. asiatica. The morphological changes of metacestodes were observed. The recovered cysticerci were fed to gerbils, hamsters and humans, to check for their infectivity. Tapeworms were recovered from gerbils and hamsters fed with 20 to 45 week-old cysticerci, and proglottids excretions were observed in human volunteers fed with 45 week-old cysticerci. However, no tapeworms were recovered from gerbils fed with 10 week-old cysticerci. Our results suggest that T. s. asiatica oncospheres needed more than 20 weeks to develop to maturity in SCID mice to be infective to both their natural and alternative definitive hosts.

Studies on abnormality of metacestodes and adult worms of Taenia solium and Taenia saginata asiatica in rodents and pigs

Abnormalities are not uncommon in Taenia saginata and T. solium. After examining 328 mature proglottids from 2 adult worms from two experimentally infected hamsters, 13 (4.0%) were found to have no genital pore but with numerous testes and several vas efferents; 1 (0.3%) one genital pore with one reproductive system; 12 (3.7%) one on each side with two sets of reproductive system; 17 (5.2%) two on one side with 2 sets of reproductive system; 8 (2.4%) one on one side and two on the other side with 3 sets of reproductive system; 2 (0.6%) two on each side with 4 sets of reproductive system; 4 (1.2%) three on one side with 3 sets of reproductive system, and 4 one on one side and three on the other side with 4 sets of reproductive system. Nine evaginated abnormal cysticerci of T. s. asiatica from three experimentally infected SCID mice each had two protoscoleces and a big bladder. From two experimentally infected pigs, one abnormal cysticercus was observed to have two invaginated canals each in one end. Another one had a neck-band behind the scolex and a big bladder. This paper is not only the first report of abnormality of T. solium from hamster but also the first one of abnormal cysticerci of T. s. asiatica from pigs and mice.

Analysis of polymorphic region of GAM-1 gene in Plasmodium vivax Korean isolates

The identification, characterization and quantification of Plasmodium sp. genetic polymorphism are becoming increasingly important in the vaccine development. We investigated polymorphism of Plasmodium vivax GAM-1 (PvGAM-1) gene in 30 Korean isolates. The polymorphic region of the PvGAM-1 gene, corresponding to nt 3792-4029, was amplified using polymerase chain reaction (PCR) followed by sequencing. All of the P. vivax Korean isolates were one type of GAM-1 gene, which were identical to that of the Belem strain. It is suggested that PvGAM-1 could not be used as a genetic marker for identifying or classifying P. vivax Korean isolates. It revealed that the polymorphic pattern was acquired basically by duplication and modification or deletion event of a 33 bp-motif fragment ended by poly guanine (G) and that there were at least three complete and one partial 33 bp-motif sequences within the polymorphic region in the longest cases such as those of South Korean and Belem isolates. In addition, we clustered P. vivax isolates with parsimonious criteria on the basis of PvGAM-1 polymorphic patterns (insertion/deletion patterns).

Experimental studies on physiological and morphological aspects of Cysticercus cellulosae in pigs

Three Small-Ear-Miniature, 3 Landrace-Small-Ear-Miniature, and one Douc-Yorkshire-Landrace pigs were inoculated orally with 100 000 eggs of Zhengzhou strain or 10 000 eggs of Harbin strain of Taenia solium. A total of 3739 cysticerci were recovered from 3 Small-Ear-Miniature and 3 Landrace-Small-Ear-Miniature pigs, giving an infection rate of 85.7% and a cysticercus recovery rate of 1.1%. The predilection sites of Cysticercus cellulosae in descending order were leg muscles, abdominal muscles, thoracic muscles, liver, head muscles, diaphragm, tongue, heart, trachea, and omentum/testes. Except 2 calcified cysticerci in the tongue, 2 in the heart, and 176 in the liver, the remaining cysticerci were all alive. The greatest number of cysticerci per 100 g of muscles or viscera was found in the head muscles, followed by the leg, diaphragm, heart, tongue, thoracic, abdominal, omentum, testes, and trachea. All cysticerci were evaginated in pig's bile after fluid was drawn out from cysticerci, whereas evagination occurred in only 83.2% of those without fluid drawing. In 364 evaginated cysticerci, the mean length and width of scolex, proglottid, and bladder, and diameter of rostellum and sucker were 826 x 747 microm, 5,370 x 1,734 microm, 2,885 x 3,002 microm, 155 microm, and 253 microm, respectively. In the protoscolex, the mean number of segments was 33. Each cysticercus had 2 rows of rostellar hooks on the scolex, and the mean length and width of inner and outer hooks were 151 x 18 microm and 117 x 14 microm, respectively. The number of paired hooks ranged from 10 to 18.

Current status of imported parasitic infection among foreign workers in northern Taiwan (1999-2000)

In the present study, a simple, economic and practical technique was employed for stool examination. Of a total of 6,146 fecal samples from foreign workers in Northern Taiwan between 1999 and 2000 were examined, 615 were found to be positive for parasitic infection and the overall infection rate was 10%. Newly arriving foreign workers had a significantly higher infection rate (15%) than those who had worked in Taiwan for 6-12 months (8%). The foreign workers came from Indonesia, Philippines, Thailand, Malaysia, and Vietnam. Except for the small number of workers from Malaysia which was not included, the infection rate order by nationality was Vietnamese (21%) > Indonesian (13%) > Philippino (10%) > Thai (4%). The female examined workers were about 3-fold of males and their infection rate (11%) was also significantly higher than the males (5%). The order of rates by age was 20-30 years (11%) > 31-40 years (8%) > 41-50 years (5%). According to the species of parasites, 569 foreign workers were infected with 1 species (9%) > with 2 species (0.7%) > with 3 species (0.1%). Totally, 14 species (10 helminths including 1 plant nematode, Heterodera and 4 protozoa; hookworm might include 2 or 3 species, but counted as one species here) were found, of which 10 species were pathogenic (9 helminths and 1 protozoa) and 4 non-pathogenic. Foreign workers from Indonesia harbored 12 species of parasites > from the Philippines, 9 species > from Thailand, 8 species > from Vietnam, 7 species.

Structural and functional sex differences in the human hypothalamus

Sex differences in the brain may be the basis not only for sex differences in reproduction, gender identity (the feeling of being male or female), and sexual orientation (heterosexuality vs homosexuality), but also for the sex difference in prevalence of psychiatric and neurological diseases ( Swaab and Hofman, 1995 ). In this brief article we discuss a few examples of structural and functional sex differences in the human brain.

Experimental studies on small hooks preceding large hooks in the growth and development of Taenia solium metacestodes

In the present study, we have determined the growth and development pattern of rostellar hooklets of Taenia solium cysticerci (Zhengzhou and Harbin strains) in three pigs (1 SEM and 2 L-SEM strains) 89-196 days post experimental infection. A total of 3,675 cysticerci were collected from 3 pigs, 3,007 (82%) of 3,675 cysticerci were evaginated by enzyme method. 439 (15%) evaginated cysticerci were carefully examined and measured after dehydration, staining, and mounting on microscopic slides. Among 439 cysticerci, 234 (53%) had pair rostellar hooks, 88 (20%) with unpair hooks, 60 (14%) only small (outer row) hooks, and 57 (13%) no hooks including 34 hooks were completely dropped and 23 no hooks developed. The number ranged from 10 to 17 pairs for pair hooks and 1 to 29 for unpair ones. The length and width of rostallar hooks on the scolex of cysticerci were usually larger in the pig with longer infection time. Moreover, cysticerci with pair and unpair rostellar hooks had only small hooks and no hooks were present on their scolices. However, cysticerci with only large (inner row) hooks were not found. These findings indicate that the growth and development of small hooks precedes that of the large hooks in the formation of the two-row pattern rostellar hook in Cysticercus cellulosae.

Analysis of polymorphic regions of Plasmodium vivax Duffy binding protein of Korean isolates

The present study was designed to investigate polymorphism in Duffy binding protein (DBP) gene of Plasmodium vivax isolates of Korea. Thirty samples were obtained from P. vivax patients in Yonchon-gun, Kyonggi-do in 1998. The PCR products of the samples were subjected to sequencing and hybridization analyses of the regions II and IV of P. vivax DBP gene. Two genotypes, SK-1 and SK-2, were identified on the basis of amino acid substitution and deletion. The genotype of 10 isolates was SK-1 and that of 20 isolates was SK-2. Most of the predicted amino acids in the region II of DBP gene were conserved between the Korean isolates and Belem strain except for 4-5 amino acid substitutions. In the region IV of DBP, a 6-bp insert that was shown in the Sal-1 allele type was found in SK-1, and a 27-bp insert that was shown in the Papua New Guinea allele type was found in SK-2. In conclusion, the present findings suggest that two genotypes of P. vivax coexist in the endemic area of Korea.

Direct determination of sinigrin in mustard seed without desulfatation by reversed-phase ion-pair liquid chromatography

Reversed-phase ion-pair liquid chromatography has been investigated for directly analyzing sinigrin in mustard seed without desulfatation. After extraction by phosphate buffer (pH 7.0) from the grind-pastes of inactivated-myrosinase mustard seeds, sinigrin was first isolated through deproteinization and centrifugation, followed by filtration and injection into the chromatographic system. A reversed-phase C18 column was used to separate the sinigrin with an eluent of acetonitrile (ACN)-water (20:80) containing 0.02 M tetrabutylammonium (TBA) as the counter ion at pH 7.0. Detection was carried out with an UV detector operated at 227 nm. Factors affecting the chromatographic separation and quantitative determination, such as concentrations of TBA and ACN, and pH, were studied. The linear dynamic range is larger than three orders of magnitude and the detection limit is 0.045 mg/L. The RSD is around 3% and the recovery is 85% (3% RSD, n = 3).

Parasitic infections among the aborigines in Taiwan with special emphasis on Taeniasis asiatica

According to the results obtained by our laboratory and the Department of Parasitology, Taipei Medical College, from 1995 to 1998, the overall infection rate of enterobiasis was 16% (4-29%) among 4,426 primary school students at 64 schools in 13 mountainous districts of 10 counties, and the infection rate of head louse infestation was 12% (3-26%) among 5,121 students. A continuous series of field studies on epidemiology and chemotherapy of taeniasis asiatica have been conducted between 1971 and 1992 among 27,359 aborigines in 88 villages of 14 districts in 10 counties and 3,104 were found to be infected, giving an overall infection rate of 11%. Laboratory studies have been performed on the morphology, intermediate hosts, experimental infection, immunology and molecular biology. Moreover, development of Taiwan Taenia in one of 3 volunteers has been successfully demonstrated since 1988. Moreover, the domestic pig was identified as the intermediate host of Taiwan Taenia as in the classical T. saginata (Poland strain). Most of cysticerci were developed in or on the parenchyma of liver. The results indicated that Taiwan Taenia is different from classical T. saginata. It has been named as T. s. asiatica. Moreover, the classical T. saginata was renamed as T. s. saginata. This paper summarizes findings and reviews those reported by our laboratory. In addition, the clinical manifestations and eating habits of the aborigines are also discussed.

Rodent model for long-term maintenance and development of the viable cysticerci of Taenia saginata asiatica

Although oncospheres of Taenia saginata asiatica can develop into cysticerci in immunodeficiency, immunosuppressed, and normal mice, no detailed information on the development features of these cysticerci from SCID mice is available. In the present study, the tumor-like cyst was found in the subcutaneous tissues of each of 10 SCID mice after 38-244 days inoculation with 39,000 oncospheres of T. s. asiatica. These cysts weighed 2.0-9.6 gm and were 1.5-4.3 cm in diameter. The number of cysticerci were collected from these cysts ranged from 125 to 1,794 and the cysticercus recovery rate from 0.3% to 4.6%. All cysticerci were viable with a diameter of 1-6 mm and 9 abnormal ones each with 2 evaginated protoscoleces were also found. The mean length and width of scolex, protoscolex, and bladder were 477 x 558, 756 x 727, and 1,586 x 1,615 microns, respectively. The diameters of suckers and rostellum were 220 microns and 70 microns, respectively. All cysticerci had two rows of rostellar hooks. These findings suggest that the SCID mouse model can be employed as a tool for long-term maintenance of the biological materials for advanced studies of immunodiagnosis, vaccine development, and evaluation of cestocidal drugs which would be most benefit for the good health of the livestocks.

Capillaria hepatica: a spurious case with a brief review

A 12-year-old Bunun aboriginal school student in Sanmin District Kaohsiung County, Southern Taiwan, was found to have Capillaria hepatica eggs in the feces during a survey on intestinal parasitic infection in 1997. Moreover, this student was also infected with Trichuris trichiura and Ascaris lumbricoides. The C. hepatica eggs were light yellowish-brown in color, 54 (40-60) microns in length and 29 (25-35) microns in width with a 3 (3-4) microns thick shell and two colorless egg plugs 7 (5-9) x 6 (5-8) microns. This is the eighth case of human spurious C. hepatica infection in Taiwan. In addition to the reporting of this case, the genuine and spurious infections of C. hepatica in humans as well as its infection in rats around the world are briefly reviewed.

Apoptosis during sexual differentiation of the bed nucleus of the stria terminalis in the rat brain

The bed nucleus of the stria terminalis (BST) in the rat forebrain differs between males and females. To test whether apoptosis may contribute to the development of sex differences in the BST, the incidence of apoptosis was determined in sham-treated males and sham-treated females sacrificed on postnatal days (PN) 2, 4, 6, 8, 10, and 12 (PN 1 being day of birth). More apoptotic nuclei were found in the principal nucleus of the BST (BSTpr) in females than in males, whereas the reverse was true for the lateral division of the BST (BSTl). Moreover, the volume of the BSTpr was larger in males than in females, whereas there was no sex difference in the volume of the BSTl. Our results also confirmed earlier reports indicating that the incidence of apoptosis in the central part of the medial preoptic nucleus (MPNc) is higher in females than in males. No sex difference in apoptosis was found in the ventromedial hypothalamus (VMH) and paraventricular nucleus (PVN). The volume of the MPNc and VMH was larger in males than in females, whereas the PVN volume did not differ between males and females. To test whether sex differences in neonatal levels of gonadal steroids may cause sex differences in the incidence of apoptosis in the BSTpr, the incidence of apoptosis was compared between castrated males and females that were treated with testosterone propionate or vehicle on the day of birth. In the BSTpr of gonadal steroid-treated animals, the incidence of apoptosis was lower when compared to animals treated with vehicle, which was also true for the MPNc. These results are consistent with the hypothesis that gonadal steroids contribute to the sexually dimorphic differentiation of the BST by controlling the incidence of apoptosis.

Sexual development of Taenia solium in hamsters from rodent-derived cysticerci

In order to determine whether Taenia solium can be maintained in the laboratory using rodents as definitive hosts, six nude rats, 20 immunosuppressed Mongolian gerbils and 20 immunosuppressed Syrian hamsters were each inoculated through a stomach tube with three cysticerci recovered from SCID mice. No adult worms of T. solium were found in the intestinal tract of any of these 46 rodents. In addition, five immunosuppressed Syrian hamsters were fed with the same number of cysticerci enclosed in rodent muscles from SCID mice. Two of these hamsters were found to be infected 40 days post-infection, each harbouring a sexually developed worm in the intestinal tract. Although no eggs were produced, prepatent infections may be possible if a longer time was allowed for worm development. Moreover, the maintenance of the life cycle of T. solium in the laboratory using the rodent model can be established.

Oncospheres of Taenia solium and T. saginata asiatica develop into metacestodes in normal and immunosuppressed mice

Normal and immunosuppressed mice were infected with oncospheres of Taenia saginata asiatica and T. solium. Although normal ICR mice were not susceptible to these two parasites, cysticerci were recovered from the immunosuppressed ones following venous injection. For T. s. asiatica, immunosuppressed ICR mice had an infection rate of 12.5% and six cysticerci of this parasite were recovered from three males. After injection of T. solium oncospheres, a high infection rate of 57% was obtained and 23 cysticerci were collected from 13 male immunosuppressed ICR mice. The immunosuppressed C57 mice had the highest infection rate (100%) and cysticercus recovery rate (2.4%) for T. solium. The infection rate and cysticercus recovery rate in six normal C57 mice were 40% and 3% respectively. The immunosuppressed ICR, Balb/c and C3H mice were also susceptible to T. s. asiatica.

Prevalence and treatment of Pediculus capitis infestation among aboriginal school children in northern Taiwan

In the present study, pediculosis was investigated among a total of 2,725 children from 35 primary schools in Hsiulin District of Hualien County, Jenai District of Nantou County, Wulai District of Taipei County, Chienshih District of Hsinchu County, Fushing District of Taoyuan County, and Nanao District of Ilan County. The overall infestation rate was 12.8%. The rates by districts were 19.7%, 17.3%, 16.7%, 15.1%, 7.9%, and 3.0%, respectively. The pediculicides including Nix (permethrin 1%) 56 gm/tube, Para aerosol (bioallethrin 0.66%) 90 gm/tube, and Perioderm (malathion 1%) cream shampoo 40 gm/tube were used to treat the head louse infestation in 83, 91, and 103 children; the cure rates were 97.3%, 94.1%, and 93.4%, respectively. No significant differences were found in these rates. The reactions were slight and transitory. A total of 636 lice was collected from the hair using fine-toothed combs before treatment and from the used towels after treatment of children in Wulai, Chienshih, Hsiulin, and Jenai Districts. Each child was found infested with a mean of 7.7 lice. The mean intensity of infestation was highest in Jenai (9.3) and Chienshih (8.7) came next. Wulai (3.7) and Hsiulin (3.6) had lower intensities.

Rate-distortion-constrained subband video coding

This paper introduces a subband video coding algorithm for operation over a continuum of rates from very low to very high. The key elements of the system are statistical rate-distortion-constrained motion estimation and compensation, multistage residual quantization, high order statistical modeling, and arithmetic coding. The method is unique in that it provides an improved mechanism for dynamic spatial and temporal coding. Motion vectors are determined in a nontraditional way, using a rate-distortion cost criterion. This results in a smoother and more consistent motion field, relative to that produced by conventional block matching algorithms. Control over the system computational complexity and performance may be exercised easily.

[Seroepidemiology of Toxoplasma gondii infection among Atayal aborigines and local animals in Nan-ao district, Ilan county and Jen-ai district, Nan-tou county, Taiwan]

In this study, latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies of Atayal aborigines and local animals in Nan-ao district, Ilan county and Jen-ai district, Nan-tou county as a measure of exposure to the Toxoplasma gondii. Out of 422 Atayal aborigines and 64 different animals were tested in Nan-ao district and 82 Atayal children in Jen-ai district were also screened, the positive rates for sera anti-toxoplasma antibodies were 21.8%, 17.2% and 15.9%, respectively. In Nan-ao district, neither were the positive rates significantly different in males (22.1%) and females (21.4%), nor in humans (21.8%) and dogs (19.6%) (P > 0.05). The seroprevalence in adults (28.3%) was significantly higher than that in children (18.7%) (P < 0.05), and the highest seropositive rate (38.1%) was in the age group 50-59 years and the lowest (7.7%) was in the age group 1-9 years. In general, the age pattern of prevalence is consistent with increasing duration of exposure to Toxoplasma gondii with age. For animals, the seropositive rate in dogs (19.6%) was also significantly higher than that in wild rats (7.7%) (P < 0.05). No significant difference in seropositive rate of Atayal children was observed between Nan-ao and Jen-ai districts (P > 0.05).

Seroprevalence of Toxoplasma gondii antibodies among Atayal aboriginal people and their hunting dogs in northeastern Taiwan

Atayal aborigines, living at an altitude of 1,500-1,600 m in northeastern Taiwan, still hunt for wild animals with the help of hunting dogs. In this study, the latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies in this community as a measure of their exposure to Toxoplasma gondii. The positive rates for sera anti-toxoplasma antibodies were 21.8% and 19.6%, respectively, in 422 Atayal and 51 hunting dogs tested. Neither of the positive rates were found to be significantly different between male (22.1%) and female Atayal (21.4%), or between humans (21.8%) and dogs (19.6%) (P > 0.05) when compared by the Chi-Squared test (chi 2-test). A significant difference was observed between the positive rates in adults (28.3%) and children (18.7%) (P < 0.05), and the age pattern of prevalence is consistent with an increasing duration of exposure to Toxoplasma gondii with age. The consumption of raw liver of wild animals or insufficiently cooked meat may be the major mode of transmission of toxoplasmosis in Atayal.

Taenia saginata asiatica: epidemiology, infection, immunological and molecular studies

The taeniasis in East Asia has a special epidemiological pattern: people eat meat and/or viscera of pigs and acquire infection of Taenia saginata-like tapeworms. However, cysticercosis is more often found in pigs than cattles. In order to elucidate the taxonomic status of this parasite, we have conducted extensive field surveys, experimental infections, and morphological as well as immunological studies since 1981. After obtaining sufficient information from our studies, we finally came to the conclusion that the T. saginata-like tapeworm in Asia is a new subspecies of T. saginata and was named as T. saginata asiatica. The classical T. saginata was renamed as T. saginata saginata. In this paper, we provide the history of T. s. asiatica in Asia.

[Seroepidemiology of Toxoplasma gondii infection among dogs in Taipei, Taiwan]

Seroprevalence of toxoplasmosis in dogs was investigated in Taipei from July 1995 to June 1996 by the latex agglutination assay. A total of 289 serum samples were taken from stray and domestic dogs as well as from dogs in randomly selected animal hospitals and pet stores. The overall seroprevalence among all dogs was 24.6% (71/289). With regard to the source of the dogs, the seropositivity was 15.4% (10/65) for dogs in animal hospitals, 16.3% (7/43) for dogs in pet stores, 15.5% (11/71) for domestic dogs and 39.1% (43/110) for stray dogs. The seropositivity of stray dogs was significantly higher than that of the domestic dogs (P < 0.05). However, there was no significant difference among the randomly selected places or dog strains (P > 0.05).

[Larval distribution in different organs of ICR strain mice infected with Toxocara canis]

In this study 80 ICR mice were infected per os with 260 embryonated Toxocara canis eggs each through a stomach tube. Ten mice were sacrificed at weekly intervals over an eight-week period. Internal organs including livers, lungs, hearts, spleens, kidneys, brains, and carcasses were pooled separately and T.canis larvae from each category treated with artificial digestive fluid were recovered and later collected by the Baermann technique. Larval distributions at a given week in different organs or in a given organ at different weeks were compared and analyzed. Results revealed that total larval recovery increased from week one (11.6%) to four(19.7%); thereafter it decreased gradually and dropped to 13.4% by week eight. Larval distribution in different organs varied with time. No larvae were recovered from the heart or spleen during the study period, except for a small number recovered from the spleen in the 4th and 5th weeks after infection. In general, the larvae were recovered mainly from the brain, carcass and liver. Larval recovery from the liver was high in the first two weeks (4.5% and 3.6%, respectively) and in week 4(5.6%). Recovery from the brain increased drastically in week 4(6.8%) and remained high. Recovery from the carcass increased with time. In the case of the lungs, a sharp peak was observed in week 3(4.8%), but recovery from the kidneys was low (0.7-1.6%). Our results indicated that the ICR strain mouse is also a suitable animal model for the study of toxocariasis in paratenic hosts.

Survival of Taenia solium cysticerci in carcasses of pigs kept at 4 C

In the present study, the survival of cysticerci of Taenia solium in carcasses of 1 Small-Ear-Miniature and 2 Landrace Small-Ear-Miniature pigs kept in a refrigerator at 4 C was determined. The viability of the cysticerci was determined by observing evagination and active movement of the scolex under a fluorescent light after digestion in pig bile. Although no viable cysticerci were found after day 30, 58.8% cysticerci survived between day 26 and day 30. Moreover, more than 80% of the cysticerci were viable between day 1 and day 25. These findings indicate that taeniasis solium can be transmitted through eating raw or undercooked pork or viscera of pigs following refrigeration at 4 C for less than 30 days.

Sociocultural factors and local customs related to taeniasis in east Asia

Taeniasis is an important medical and economic problem in many countries in East Asia. According to our estimation, there is an annual loss of US$18,673,495, US$13,641,021, and US$2,425,500 due to taeniasis in the mountainous areas of Taiwan, Cheju Island of Korea, and Samosir Island of Indonesia, respectively. Although taeniasis and cysticercosis due to Taenia solium have been reported, T. saginata asiatica is the dominate species in part of the world, especially in the mountainous and remote areas where the inhabitants are fond of eating raw or undercooked meat and/or viscera of domestic or wild animals. Therefore, sociocultural factors and local customs are the determinants in the transmission of taeniasis. In this paper, local customs and sociocultural factors including local dishes, accidental infection during dish preparation, and treatment for anaemia of children in the countries of East Asia were reviewed.

DNA damage distribution in the human brain as shown by in situ end labeling; area-specific differences in aging and Alzheimer disease in the absence of apoptotic morphology

DNA damage has been proposed to underlie neuronal degeneration in aging and Alzheimer disease (AD). To determine the histological distribution of DNA damage, in situ end labeling (ISEL) was applied as a marker for DNA breaks on 4 differentially affected brain areas. Occipital cortex showed considerable variation between cortical layers and between patients. Temporal cortex displayed little ISEL-labeling in controls, and in AD, surprisingly. In the hippocampus, which is strongly affected in AD, many ISEL-positive nuclei and glialike cells were found in AD as compared with controls. The hypothalamic supraoptic and paraventricular nuclei showed little DNA-damage, whereas the nucleus basalis was often, but not always, labeled by ISEL. In contrast to others, no apoptotic morphology was observed, only necrotic morphology. Our results in relation to postmortem delay indicate that, area dependent, increased DNA vulnerability may occur in AD. Furthermore, the distribution of DNA damage in cortex differs from that of plaques and tangles, suggesting that these 3 phenomena are, in principle, independent. Whether the enhanced level of hippocampal DNA breaks in AD underlies, or rather is a consequence of, previous degenerative changes in this brain area remains to be established.

Vaccination trials against Taiwan Taenia eggs in pigs injected with frozen oncospheres of Taiwan Taenia, Korea Taenia, T. saginata or T. solium

When Small-Ear-Miniature pigs subcutaneously injected once with frozen oncospheres of Taiwan Taenia, Korea Taenia, T. saginata or T. solium emulsified with Freund's complete adjuvant (1.6 x 10(4)/0.4 ml) were challenged orally with 1.6 x 10(4) viable eggs of Taiwan Taenia 41 days later, they all showed strong resistance compared with pigs vaccinated with T. solium. Most pigs (5/8) of the former 3 groups harboured no cysticerci. The number of cysticerci was 5.5 +/- 9.1 (mean +/- S.D.), whereas pigs of the T. solium group and control group harboured 160 +/- 30.1 and 661 +/- 637.2 cysticerci, respectively. All cysticerci recovered from vaccinated pigs and most cysticerci in control pigs were degenerated or calcified at 36-55 days after oral egg challenge. These results strongly suggest that oncospheres of Taiwan Taenia and Korea Taenia are very similar to T. saginata in their immunogenicity in pigs.

In vitro hatched oncospheres of Asian Taenia from Korea and Taiwan develop into cysticerci in the peritoneal cavity of female scid (severe combined immunodeficiency) mice

In vitro hatched (but not activated) oncospheres of Asian Taenia obtained in Korea and Taiwan, prepared by the sodium hypochlorite method, rinsed with sterile PBS several times and adjusted to 5 x 10(4)/0.5 ml PBS, were injected intraperitoneally or subcutaneously into male or female scid mice of 3 different strains. When these scid mice were sacrificed 4 months later, the females harboured fully developed cysticerci either in the peritoneal cavity or under the back skin, whereas males did not. All cysticerci from the peritoneal cavity were easily recovered by rinsing the abdomen with PBS. Although most cysticerci recovered from pig liver usually become calcified within 1-2 months, in female scid mice they all increased in size and were viable. Intraperitoneal (i.p.) injection of in vitro hatched oncospheres is recommended for easier recovery of Asian Taenia metacestodes in laboratory animals.

Human babesiosis in Taiwan: asymptomatic infection with a Babesia microti-like organism in a Taiwanese woman

An asymptomatic Babesia infection was confirmed by laboratory diagnoses. The intraerythrocytic protozoan (designed TW1) isolated from a 51-year-old Taiwanese woman appeared to be morphologically consistent with small-form piroplasm, and measurements indicated that it had a body size of 1.5 to 2.5 microm in diameter. The typical features of ring, binary, and tetrad forms were observed in Giemsa-stained thin blood smears. A persistent and low-grade parasitemia was established after hamster inoculation. Indirect immunofluorescent-antibody reactivities indicate that this strain (TW1) of Babesia was serologically related to, but not identical to, the Babesia species (B. microti) that infects rodents. Antibody titers in the patient's sera combined with the clinical symptoms suggested that the present case was a chronic and subclinical babesial infection. A neighborhood human serologic survey indicated that the infection may have been acquired accidentally from an infected rodent and localized within the same family. Indeed, rodents from areas around the neighborhood were trapped, and a high prevalence (83%) of babesial infection was observed. The possible vector responsible for the transmission remains to be identified.

Human Taenia eggs develop into cysticerci in scid mice

The intermediate hosts for Taenia saginata and T. solium are cattle and pigs (and humans for the latter), respectively. In vitro-hatched (but not activated) oncospheres of both Asian Taenia (T. saginata asiatica, a new subspecies of T. saginata or T. asiatica, a new species) and T. solium injected subcutaneously into the backs of mice with severe combined immunodeficiency (scid) developed into fully matured cysticerci. Five-month-old metacestodes of Asian Taenia had no hooklets and were bigger in size than those previously reported and similar to those of T. saginata. Their morphology suggested that the cysticerci were more advanced than those in the intermediate host animals. It is suggested that scid mice are valuable experimental animal models for studying human taeniid cestode infections.

Ectopic locations of Taenia saginata asiatica cysticerci in the abdominal cavity of domestic pig and monkey

Eleven Small-Ear-Miniature pigs, 1 Landrace Small-Ear-Miniature pig, and 1 monkey (Macaca cyclopis) were infected experimentally with eggs of Taenia saginata asiatica. They were found to harbor cysticerci on the liver surface, each with a thin, whitish fiber connecting to another location in the same lobe, or to other lobes of the liver; some were also connected individually to the diaphragm, abdominal muscles, and gall bladder with a short, thin fiber. Moreover, they also harbored extrahepatic cysticerci. Most of these were observed on the omentum and in the peritoneal cavity, except for some suspended individually in the abdominal cavity by a long, thin, whitish fiber. The origin of the extrahepatic cysticerci and whitish fibers is probably from the surface of the liver of the host.

Conditional entropy-constrained residual VQ with application to image coding

This paper introduces an extension of entropy constrained residual vector quantization (VQ) where intervector dependencies are exploited. The method, which we call conditional entropy-constrained residual VQ, employs a high-order entropy conditioning strategy that captures local information in the neighboring vectors. When applied to coding images, the proposed method is shown to achieve better rate-distortion performance than that of entropy-constrained residual vector quantization with less computational complexity and lower memory requirements, moreover, it can be designed to support progressive transmission in a natural way. It is also shown to outperform some of the best predictive and finite-state VQ techniques reported in the literature. This is due partly to the joint optimization between the residual vector quantizer and a high order conditional entropy coder as well as the efficiency of the multistage residual VQ structure and the dynamic nature of the prediction.

Experimental studies on the pathway for migration and the development of Taiwan Taenia in domestic pigs

The pig is the most favorable experimental intermediate host of Taiwan Taenia. Cysticerci in infected pigs are located in the liver except for a few extrahepatic ones. The present study was designed to investigate the pathway of migration of the oncospheres of Taiwan Taenia in the pig. In the first group, each of 5 Small-Ear-Miniature (SEM) and one Landrace-Small-Ear-Miniature (L-SEM) pigs were injected with 5000 hatched oncospheres into the ear vein. Three SEM and one L-SEM pigs were found to harbor 88 degenerated or calcified cysticerci only in the liver 51-81 days after injection. In the second group, each of 3 L-SEM pigs were injected with 5000 hatched oncospheres into the jugular vein. One of the 3 pigs was found to have 5 cysticerci (2 mature and 3 degenerated or calcified) only in the liver at 89 days post-injection. In the third group, each of 4 SEM, three L-SEM, and 3 L-SEM pigs were injected with 10,000, 10,000, and 5000 hatched oncospheres, respectively, directly into the portal vein after surgical opening of the abdominal cavity. All 10 pigs were found to be infected with a total of 1088 cysticerci (44 mature and 1044 degenerated or calcified) only in the liver 23-62 days after injection. Although the sites of injection in these three groups were different, the liver was the only final location of the cysticerci. These findings give strong evidence that the oncospheres migrate to the liver through the venous circulation and develop in this organ.

A jointly optimized subband coder

The mainstream approach to subband coding has been to partition the input signal into subband signals and to code those signals separately with optimal or near-optimal quantizers and entropy coders. A more effective approach, however, is one where the subband coders are optimized jointly so that the average distortion introduced by the subband quantizers is minimized subject to a constraint on the output rate of the subband encoder. A subband coder with jointly optimized multistage residual quantizers and entropy coders is introduced and applied to image coding. The high performance of the coder is attributed to its ability to exploit statistical dependencies within and across the subbands. The efficiency of the multistage residual quantization structure and the effectiveness of the statistical modeling algorithm result in an attractive balance among the reproduction quality, rate, and complexity.

Morphological description of Taenia saginata asiatica (Cyclophyllidea: Taeniidae) from man in Asia

In order to clarify the taxonomic status of the Taenia saginata-like tapeworm in East Asia, the morphological characteristics of the adult and cysticercus of classical T. saginata (American, Swiss and Poland strains) and the Taiwan Taenia were compared in the present study. The morphologic characteristics of these two parasites are very similar. The protoscolex of cysticercus of the Taiwan Taenia has a sunken rostellum while that of classical T. saginata has only an apical pit. In addition, the rostellum of the Taiwan Taenia cysticercus is usually surrounded by two rows of rudimentary hooklets. However, this structure is rarely found in classical T. saginata. Based on the results of molecular studies and morphological characteristics, the T. saginata-like tapeworm in East Asia represents a subspecies of T. saginata, named T. saginata asiatica.

Microwave-enhanced in situ end-labeling of fragmented DNA: parametric studies in relation to postmortem delay and fixation of rat and human brain

In situ end-labeling (ISEL) identifies DNA fragmentation in apoptotic or necrotic nuclei in tissue sections. However, application of ISEL on human brain requires conservation of DNA integrity during the postmortem delay (PMD) and good accessibility of fragmented DNA after (prolonged) tissue fixation. We therefore investigated ISEL in relation to PMD and fixation in rat and human brain. Application on a unilateral lesion model in perfused rat brain revealed that prolonged post-fixation strongly diminished ISEL results. However, microwave pre-treatment can counteract these masking effects without inducing nonspecific labeling contralaterally. On the other hand, in briefly post-fixed, perfused brain or immersion-fixed rat and human PMD brain, microwave pre-treatment was deleterious and induced strong nonspecific labeling. In young rat brain, PMD did not influence the low numbers of apoptotic nuclei until 24 hr PMD, when massive nuclear labeling occurred. In human cortex, DNA fragmentation patterns were independent of duration of fixation or PMD and were already present from 4.25 hr PMD onwards. Our data suggest that ISEL on human brain represents antemortem DNA damage rather than PMD artifacts. Furthermore, microwave pre-treatment appears beneficial only in particular fixation conditions.