Usefulness of normal saline for sealing the needle track after CT-guided lung biopsy.

AIM: To determine whether the use of normal saline for sealing the needle track can reduce the incidence of pneumothorax and chest tube placement after computed tomography (CT)-guided lung biopsy. MATERIALS AND METHODS: A prospective, randomised, controlled trial enrolling 322 patients was conducted. All patients were randomly assigned to one of two groups: those in whom the needle track was not sealed with normal saline (n=161, Group A) and those who did receive normal saline (n=161, Group B). CT-guided biopsy was performed with coaxial technique. Normal saline, which ranged from 1-3 ml, was injected while the trocar needle was being withdrawn. Patient characteristics, lesion, and procedure variables were analysed as potential risk variables for occurrence of pneumothorax and chest tube placement. RESULTS: The incidence of pneumothorax was 26.1% in Group A and 6.2% in Group B (p<0.001). Nine patients in Group A and one patient in Group B required chest tube placement (p=0.010). Using multiple logistic regression analysis, smaller lesion size, greater needle-pleural angle, longer lesion-pleural distance, presence of emphysema, and no sealing the needle track with normal saline were significantly associated with an increased risk of pneumothorax, and that the latter three factors were also associated with an increased risk of pneumothorax requiring chest tube placement. CONLUSION: Normal saline for sealing the needle track significantly reduces the incidence of pneumothorax and prevents subsequent chest tube placement after CT-guided lung biopsy.

Factors influencing diagnostic yield of CT-guided percutaneous core needle biopsy for bone lesions.

AIM: To evaluate the factors influencing diagnostic yield of computed tomography (CT)-guided percutaneous core needle biopsy (CNB) for bone lesions. MATERIALS AND METHODS: Between September 2005 and July 2011, 162 consecutive CT-guided CNB procedures were performed in 155 patients. The variables analysed were age, sex, lesion location, lesion type, lesion size, specimen size, biopsy needle gauge, and individual radiologist. The factors influencing diagnostic yield of CT-guided percutaneous CNB for bone lesions were determined by multivariate analysis of variables. RESULTS: The diagnostic yield was 81.5%. Diagnostic yield was 89.9% for lytic bone lesions and 48.5% for sclerotic bone lesions (p < 0.001), and 89.2% for lesions ≥3 cm and 73.4% for lesions <3 cm (p = 0.010). The significant factors influencing diagnostic yield of CT-guided percutaneous CNB for bone lesions were lesion type [p < 0.001; odds ratio (OR) for a lytic lesion was approximately 12 times higher than that for a sclerotic lesion; 95% confidence interval (CI): 4.22-34.01], and lesion size (p = 0.012; OR for a lesion size ≥3 cm was about five-times higher than that for a lesion size <3 cm; 95% CI: 1.42-16.71). CONCLUSION: Lesion type and lesion size are determining factors in diagnostic yield. The higher diagnostic yield is correlated with lytic lesion and lesion size ≥3 cm.

Can diffusion-weighted imaging be used to differentiate brain abscess from other ring-enhancing brain lesions? A meta-analysis.

AIM: To explore the role of diffusion-weighted imaging (DWI) in the discrimination of brain abscess from other ring-enhancing brain lesions through meta-analysis. MATERIALS AND METHODS: The PUMBED, OVID, and China National Knowledge Infrastructure (CNKI) databases, from January 1995 to March 2013, were searched for studies evaluating the diagnostic performance of DWI in the discrimination of brain abscess lesions. Using the data collected, pooled sensitivities and specificities across studies were determined, positive and negative likelihood ratios (LR) were calculated, and summary receiver operating characteristic (SROC) curves were constructed. RESULTS: A total of 11 studies fulfilled all of the inclusion criteria and were considered for the analysis. The pooled sensitivity values and pooled specificity values including 95% confidence intervals (CI) were 0.95 (0.87-0.98) and 0.94 (0.88-0.97). The pooled positive LR (95% CI) was 4.13(2.55-6.7); the pooled negative LR (95% CI) was 0.01 (0-1.7); and the area under the curve of the symmetric SROC was 0.98. CONCLUSIONS: DWI has high sensitivity and specificity for the differentiation of brain abscess from other intracranial cystic mass lesions.

Observation of topological superconductivity in a stoichiometric transition metal dichalcogenide 2M-WS2.

Topological superconductors (TSCs) are unconventional superconductors with bulk superconducting gap and in-gap Majorana states on the boundary that may be used as topological qubits for quantum computation. Despite their importance in both fundamental research and applications, natural TSCs are very rare. Here, combining state of the art synchrotron and laser-based angle-resolved photoemission spectroscopy, we investigated a stoichiometric transition metal dichalcogenide (TMD), 2M-WS2 with a superconducting transition temperature of 8.8 K (the highest among all TMDs in the natural form up to date) and observed distinctive topological surface states (TSSs). Furthermore, in the superconducting state, we found that the TSSs acquired a nodeless superconducting gap with similar magnitude as that of the bulk states. These discoveries not only evidence 2M-WS2 as an intrinsic TSC without the need of sensitive composition tuning or sophisticated heterostructures fabrication, but also provide an ideal platform for device applications thanks to its van der Waals layered structure.

DNA sequence and comparative analysis of chimpanzee chromosome 22.

Human-chimpanzee comparative genome research is essential for narrowing down genetic changes involved in the acquisition of unique human features, such as highly developed cognitive functions, bipedalism or the use of complex language. Here, we report the high-quality DNA sequence of 33.3 megabases of chimpanzee chromosome 22. By comparing the whole sequence with the human counterpart, chromosome 21, we found that 1.44% of the chromosome consists of single-base substitutions in addition to nearly 68,000 insertions or deletions. These differences are sufficient to generate changes in most of the proteins. Indeed, 83% of the 231 coding sequences, including functionally important genes, show differences at the amino acid sequence level. Furthermore, we demonstrate different expansion of particular subfamilies of retrotransposons between the lineages, suggesting different impacts of retrotranspositions on human and chimpanzee evolution. The genomic changes after speciation and their biological consequences seem more complex than originally hypothesized.

Computed tomography-quantified body composition predicts short-term outcomes after gastrectomy in gastric cancer.

Background: Malnutrition is a common and critical problem that influences outcome in cancer patients. Body composition reflects a patient's metabolic profile and physiologic reserves, which might be the true determinant of prognosis. In the present study, which aimed to identify valuable new prognostic indicators, we investigated the association between computed tomography-quantified body composition and short-term outcomes after gastrectomy for gastric cancer. Methods: Skeletal muscle index, mean muscle attenuation, and ratio of visceral-to-subcutaneous adipose tissue area (vsr) were calculated from preoperative computed tomography images. Low skeletal muscle index, low mean muscle attenuation, and high vsr were respectively termed "sarcopenia," "myosteatosis," and "visceral obesity." The association of body composition with postoperative complications and serum markers of nutrition and inflammation after radical gastrectomy were analyzed. Results: The overall complication rate was significantly higher in the sarcopenia (62.5% vs. 27.3%, p = 0.001) and myosteatosis groups (38.2% vs. 4%, p = 0.002). Patients with visceral obesity had a higher incidence of inflammatory complications (20.3% vs. 6.5%, p = 0.01). Multivariate logistic regression analysis demonstrated that sarcopenia (p = 0.013), myosteatosis (p = 0.017), and low serum retinol-binding protein (p = 0.019) were independent risk factors for overall complications. Compared with control subjects, patients with sarcopenia had lower postoperative levels of serum retinol-binding protein (p = 0.007), and patients with visceral obesity had higher levels of C-reactive protein (p = 0.026). Conclusions: Sarcopenia, myosteatosis, and visceral obesity were significantly associated with increased rates of postoperative complications and affected the postoperative nutrition and inflammation status of patients with gastric cancer.

[ZHENG Wenzhuo's Yi gu (Medical Original Events) and ZHANG Binglin's Yi gu mei pi qi ze (Seven Pieces of Headnotes for Yi gu)].

Yi gu (Medical Original Events) is a rare documentation science book for textual research in traditional Chinese medicine, which makes the textual research on ancient books before the Tang Dynasty by probing its provenance and development, judging the right from wrong, citing extensively with relatively reliable evidences. Actually, many items in this work were written to refute the Confucian master Yu Yue's Fei yi lun (On Abolishment of Chinese Medicine), and, to some extent, makes contributions to defend the status of traditional Chinese medicine. ZHANG Binglin, a disciple of Yu Yue, sharply accused Yi gu of textual misconducts by commenting in his Seven Pieces of Headnotes for Yi gu. It is beneficial by mutual reference and citations.

Parasite antigens in sera and urine of patients with bancroftian and brugian filariasis detected by sandwich ELISA with monoclonal antibodies.

We developed a sandwich enzyme-linked immunosorbent assay to detect circulating parasite antigens in human lymphatic filariasis. The assay utilizes a polyclonal rabbit antifilarial antiserum to capture, and a monoclonal antibody to identify, circulating parasite antigen. Using this assay, we found that greater than 95% of sera from microfilaremic donors with bancroftian or brugian filariasis, approximately 60% of sera from microfilaremic patients with hydroceles, chyluria, or elephantiasis, and 15%-20% of sera from asymptomatic residents of filariasis-endemic areas evidently contain filarial antigens. Antigen was also detected in the urine of some microfilaremic patients. Serum levels of antigen detected with one monoclonal antibody, ES34, correlated well with microfilarial density in night blood. In contrast, less than 5% of sera from residents of areas where lymphatic filariasis is not endemic reacted in the assay, even though approximately one-third of the donors whose sera were tested were known to be infected with intestinal nematodes. The assay was designed to be flexible enough to allow the parallel use of multiple monoclonal antibodies with different specificities and simple enough to be applicable in most areas where lymphatic filariasis is endemic.

Comparison of Dot-ELISA with Sandwich-ELISA for the detection of circulating antigens in patients with bancroftian filariasis.

We compared the performance of a newly developed Dot-ELISA with that of a previously described Sandwich-ELISA to detect parasite antigens in sera from patients with bancroftian filariasis. The same monoclonal antibody and the same sera were used in both tests. In the Dot-ELISA, 67 of 70 sera from microfilaremic donors were deemed to contain filarial antigens when screened at a dilution of 1:50. End titers were 1:80-1:1280. With the Sandwich-ELISA, 64 of the same sera were positive at a dilution of 1:10 and 42 were positive at a dilution of 1:50. End titers were 1:10-1:320. The specificity of both assays was greater than 95%, but their sensitivity was remarkably different. The Dot-ELISA could detect as little as 0.055 ng/ml microfilarial antigen added to normal human sera, whereas the lower limit with the Sandwich-ELISA was 10 ng/ml parasite antigen. Additionally, the Dot-ELISA does not require radioactivity or sophisticated equipment and, therefore, can be performed in virtually all filariasis-endemic areas.

Evaluation of recombinant chitinase and SXP1 antigens as antimicrofilarial vaccines.

Prior studies indicate that a microfilarial stage-specific chitinase is a possible candidate antigen for a transmission-blocking vaccine against Brugian filariasis. The antigen is a functional enzyme that progressively appears as microfilariae mature and become able to infect and develop in a susceptible mosquito vector. It is recognized by a monoclonal antibody that reduces microfilaremia in infected animals and by a subset of sera from infected persons who remain amicrofilaremic. Immunization of jirds with recombinant chitinase induced partial protection against microfilaremia resulting from subsequent infection with Brugia malayi, but did not reduce adult worm burdens. Vaccination was much less effective when administered during the prepatent stage of infection and was ineffective when given to microfilaremic jirds. The protective epitope appears to be located close to the carboxy terminus of the chitinase molecule. Immunization of jirds with SXP1, an antigen present in multiple worm stages, also reduced microfilaremia and, in some experiments, adult worm burdens, but hyperimmunization with a recombinant filarial myosin was not protective. These observations indicate that the relative timing of immunization and infection is an important factor in the efficacy of antimicrofilarial vaccines.

Parasite antigenemia in untreated and treated lymphatic filarial infections.

To evaluate the merit of antigen detection assays as a tool to monitor the efficacy of chemotherapy for lymphatic filariasis, we serially measured antigen levels in sera from jirds infected with Brugia malayi and from humans with bancroftian filariasis. Antigenemia was detected in all animals with parasitologically proven infection and was present in jirds with prepatent or occult filariasis. Antigen levels correlated with worm burdens, and progressively declined in drug-cured animals. Treatment with diethylcarbamazine (DEC) triggered a transient increase in serum levels of filarial antigens bearing the epitope recognized by the monoclonal antibody HC 11. All patients with bancroftian filariasis became amicrofilaremic within one week after DEC treatment. Antigenemia levels slowly declined over a period of several months in all but one treated individual. Forty-two months after treatment, progressively rising antigen levels are present in 10 patients. Six of these remain amicrofilaremic; in the other 4, elevated antigenemia levels preceded or were detected at the same time as recurrent parasitemia. Periodic monitoring of antigenemia levels after treatment of patients with lymphatic filariasis can be used to identify individuals who are likely to develop recurrent microfilaremia before the parasites become detectable in blood samples, thereby allowing timely retreatment.

Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. I. Clinical and parasitologic observations.

We compared the efficacy of a single dose of ivermectin with that of a standard course of diethylcarbamazine (DEC) for the control of microfilaremia in 60 patients with bancroftian filariasis who had developed recurrent microfilaremia after each of three or more prior treatments with DEC. The study was done as a randomized, double-blind trial. Complete, but in some cases, transient clearance of microfilaremia was observed in both treatment groups. At one year, recurrent microfilaremia was present in seven patients treated with ivermectin and in five treated with DEC. Pretreatment levels of microfilaremia were significantly higher in patients who relapsed within one year after treatment than in those who remained amicrofilaremic. Side effects with both treatments were common, but mild. Febrile reactions were more frequent in the ivermectin group; localized reactions consistent with a flare-up of acute filarial disease occurred mostly in the DEC group. We conclude that ivermectin is an effective and practical alternative to DEC for treatment of recurrent microfilaremia due to bancroftian filariasis.

Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. II. Immunologic changes following treatment.

We compared the effect of a single dose of ivermectin with that of a standard course of diethylcarbamazine (DEC) on several parameters of the host's antifilarial immune response in 60 patients with bancroftian filariasis enrolled in a double-blind drug trial. All participants had measurable serum levels of antifilarial antibodies and parasite antigens at the onset of the study. Drug-induced clearance of microfilaremia was associated with a temporary increase in HC 11 antigenemia and a decrease in serum levels of antibodies to soluble filarial antigens. Antigenemia progressively declined in patients who remained amicrofilaremic after treatment, but declined and then increased in persons with recurrent microfilaremia. Treatment triggered a sustained increase in serum levels of interleukin-1, tumor necrosis factor, and interleukin-6 in all patients studied. Although ivermectin and DEC are believed to exert their antiparasite activity via different mechanisms, the same pattern of serologic changes was observed in patients treated with either drug.

High performance optical absorbance detectors based on low noise switched integrators.

Optical absorption detection is the most common analytical measurement principle in liquid phase analysis. The current state-of-the-art of commercially available detectors exhibit peak-to-peak (p-p) noise levels in the range of 1 x 10(-5)-2 x 10(-5) absorbance units (10-20 microAU). Using circuitry based on newly available switched integrator integrated circuit (IC) packages, it is possible to construct inexpensive absorbance detectors with p-p noise levels as low as 3 microAU under actual use conditions. The necessary electronics are described and performance data are reported with light emitting diodes (LEDs) as light sources. Even in the capillary format with a rectangular capillary (50 x 1000 microm cross section) with a slitwidth <50 microm and with the 1000 microm dimension as the nominal pathlength, p-p noise levels of 10 microAU are observed, from which a concentration limit of detection (LOD) of 10 nM for bromothymol blue (BTB) can be estimated with a 660 nm light source.

Monitoring of filarial antigens in jirds and patients after treatment.

We developed a sandwich ELISA with monoclonal antibodies to monitor filarial antigens in animals and patients after infection and treatment. Levels of antimicrofilarial antibodies and parasite antigens were measured periodically in 40 B. malayi infected jirds. In all animals L3 HC11 antigen was detected earlier than Mf ES34 antigen, while antimicrofilarial antibodies appeared much more slowly. These serologic changes precede the onset of patent infections. After 3 courses of treatment with DEC and M170, the levels of parasite antigen in sera and of Mf in peritoneal cavities were monitored in 23 infected jirds. In 8 jirds Mf became negative, no adult worms were found in 7 jirds and a single degenerating female worm was present in 1 jird. ES34 and HC11 were undetectable in 8/8 and 6/8 necropsy sera. Mf persisted in 11 animals, 9 jirds were necropsied, 8 contained adult worms. Detectable levels of ES34 or HC11 antigen were present in 7/9 and 8/9 from these animals. In sham-treatment, few changes were noted in control animals. Thus, parasitological findings at necropsy are correlated with the results of antigen detection assay. We analyzed serial serum samples from 32 bancroftian microfilaremia collected 1-42 months after DEC therapy. Mf resolved rapidly in all treated individuals. ES34 disappeared faster than HC11, 3 months after treatment. Levels of ES34 and HC11 antigens remained detectable or rising after treatment in 8 and 10 individuals. Four patients' Mf recurred 20-42 months after treatment. These findings show that the remaining or a rise in serum levels of antigen after therapy predicts recurrent microfilaremia in patients and additional treatment is needed.

Comparison of Dot-ELISA with Sandwich ELISA in detecting circulating antigen in patients with bancroftian filariasis.

Dot-ELISA assay was compared with standard Sandwich ELISA in detecting parasite antigen in sera from patients with bancroftian filariasis. The same monoclonal antibody and the same serum samples were used in both assays. With Dot-ELISA, 67 of 70 serum samples from microfilaremic patients were positive at a dilution of 1:50. End titers ranged from 1:80 to 1:1 280. While with Sandwich ELISA, 64 of the 70 serum samples were positive at a dilution of 1:10. End titers ranged from 1:10 to 1:320. The specificity of both assays was over 91%, but their sensitivity was markedly different. Dot-ELISA could detect as little as 0.055 ng/ml microfilarial antigen added to normal human serum, whereas the lower limit of detection by Sandwich-ELISA was 10 ng/ml parasite antigen. An additional advantage of Dot-ELISA is that it does not require radioactivity or sophisticated equipment and, therefore, can be performed in virtually all filariasis-endemic areas.

Cryopreservation of infective-stage larvae of Brugia malayi.

Third-stage larvae of Brugia malayi (Guizhou, China strain), in RPMI-1640, 6% DMSO and 15% calf serum, frozen slowly in the vapor phase of liquid nitrogen prior to emersion in liquid nitrogen, remained viable for as long as as 321 days and were infective to Mongolian jirds. All DMSO should be removed from the freezing medium to restore larval activity after freezing.

Blood meals of mosquito vectors of filariasis in Guizhou Province, China.

The blood meals of mosquito vectors of W. bancrofti and B. malayi were determined by performing CIEP of the eluant of crushed mosquitoes in filter paper against rabbit anti-human, cow and pig sera. The mosquitoes were collected from houses, cowsheds and pigpens in two counties in Guizhou Province. It was shown that all three species fed on blood from humans, cows and pigs with different preference. While An sinensis fed more on cows, Cx. fatigans and An. lesteri fed on the hosts that were nearby, i.e., Cx. fatigans caught from households fed more on humans, and those collected from cowsheds or pigpens fed more on cows and pigs, respectively.

Survival and infectivity of Brugia malayi microfilariae after cryopreservation.

Methods were studied for the cryopreservation of microfilariae of periodic Brugia malayi. RPMI-1640 tissue culture medium containing 6% dimethyl sulfoxide (DMSO) and 15% newborn calf serum was used as cryoprotectant. Samples were frozen slowly in the vapor phase of liquid nitrogen prior to emersion in liquid nitrogen (-196 degrees C). The freezing rate was -0.5 to -1.0 degrees C per minute, microfilariae remained viable for as long as, 212 and 375 days, survival rates were 94 to 98% and they were infective to Aedes togoi mosquitos. The infective larvae (L3) were obtained for 10-11 days after feeding at 28 degrees C room-temperature and the infection rate of L3 in test mosquitos was 22.4-30.6%. All DMSO should be removed from the freezing medium to restore microfilariae activity after freezing.

[Clinical research on the treatment of acute leukemia with autologous bone marrow transplantation].

38 cases of acute leukemia were treated with autologous bone marrow transplantation (ABMT). The marrow was purged with hyperthermia of 42 degrees C in vitro for one hour in microwave. Twenty-two among them were AML (CR1). Sixteen were ALL (CR1). The mean age was 26 (10-43) years. All the patients were engrafted successfully after ABMT. Mean DFS was 21 (3-69) months. Four cases relapsed at 3 to 8 months after ABMT. Two patients with ALL developed central nervous system leukemia at 12 and 15 months respectively after ABMT. The DFS and probability of relapse at 5 years were 67.8% and 16.8% respectively for all patients.