[Primary pulmonary NUT carcinoma: a clinicopathological analysis of seven cases]

Objective: To investigate the clinicopathological characteristics of primary pulmonary NUT carcinoma. Methods: A total of 7 cases of primary pulmonary NUT carcinoma were collected from Fujian Provincial Hospital (n=5), Fuzhou Taijiang Hospital (n=1) and Binzhou City People's Hospital of Shandong Province (n=1) from January 2021 to April 2023. The clinical, histopathological, and immunohistochemical features were analyzed, and NUT rearrangement were detected by fluorescence in situ hybridization (FISH) with break-apart probes. Results: Seven cases were all male with age ranging from 32 to 73 years. The main clinical manifestations were cough, expectoration and chest tightness. Microscopically, NUT carcinoma was composed of monotonous proliferation of primitive-appearing small-to-medium round cells, with few eosinophilic cytoplasm, arranged in solid sheets, nests or clusters. Abrupt keratinization was typically observed in 4 cases (4/7), with high mitotic activities and necrosis. Immunohistochemistry (IHC) showed that the tumors were positive for NUT (7/7), CK7 (4/4), CK5/6 (5/6), p40 (6/7). Ki-67 index were 30%-80%. NUT gene segregation (7/7) was detected by FISH break probes. Conclusions: Primary pulmonary NUT carcinoma is rare and highly malignant. Diagnosis depends on histopathology and IHC, with molecular detection as an adjunct for diagnosis. Pathologists should be aware of the clinicopathological characteristics to avoid misdiagnosis.

[Measuring and analysis of the shoulder circumferences of 840 adults' permanent teeth crown preparations]

Objective: To measure and analyze the shoulder circumferences of adults' permanent teeth crown preparations based on data collected through the intraoral scanning, so as to provide dental anatomy data for clinical diagnosis and analysis. Methods: Intraoral scanning data of 840 complete crown preparations were collected, and were entrusted to the World Dental Laboratory Co., Ltd. in Fuzhou between March 2021 and June 2022. Except the data of the third molar, the rest data were categorized in terms of 14 tooth positions in the upper and lower jaw (each category involved 30 samples from male group and 30 samples from female group). Image measurement software was used to measure the shoulder circumferences of permanent teeth crown preparations. And analysis was conducted to reveal the difference of shoulder circumference diameters between male and female groups. And then they were grouped according to the mean value at each tooth position, on the premise that the difference between the maximum and minimum values and the mean value of the entire group was≤±1.00 mm. Analysis were further conducted to determine the differences of shoulder circumference diameters between each dental position and the differences between male and female in the same groups. Results: Bivariate analysis of variance showed that gender had no effect on the shoulder circumference of full crown preparations (F=0.55, P=1.457), while tooth position had a significant impact on the shoulder circumference of full crown preparations (F=273.15, P<0.001). The samples were classified into 5 groups according to the mean values of shoulder circumference diameters relating to each tooth position. Statistical analysis showed that Group 1, covering maxillary lateral incisor, mandibular central incisor and mandibular lateral incisor, had shoulder circumference with diameters of (16.62±2.21) mm; Group 2, consisting of maxillary central incisor, maxillary cusp, mandibular cusp, mandibular first premolar and mandibular second premolar, had diameters of (20.78±2.48) mm; Group 3, consisting of maxillary first premolar and maxillary second premolar, had diamerters of (22.09±2.72) mm; Group 4, covering maxillary first molar, maxillary second molar and mandibular first molar, had diamerters of (30.21±2.67) mm; while group 5, with mandibular second molar alone its member, had diamerters of (31.34±3.18) mm. The difference among the 5 groups was statistically significant (P<0.05). Conclusions: Significant differences of shoulder circumference diameters could be found between different tooth positions, while at the same tooth position, the differences between male and female are not significant. The 14 tooth positions could be grouped into 5 groups according to their shoulder circumference diameters. Future research could take the grouping as reference.

[Comparison of two different methods of rapid expansion combined with maxillary protraction in the treatment of skeletal class Ⅲ malocclusion]

Objective: To compare the effect of bone-anchored versus tooth-borne rapid palatal expansion (RPE) combined with maxillary protraction in the treatment of skeletal class Ⅲ patients with maxillary hypoplasia. Methods: Twenty-six skeletal class Ⅲ patients with maxillary hypoplasia in the late mixed or early permanent dentition were selected. All the patients underwent RPE combined with maxillary protraction in the Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University from August 2020 to June 2022. The patients were divided into 2 groups. Thirteen patients were enrolled in the bone-anchored RPE group [4 males and 9 females, aged (10.2±1.7) years] and the others were in the tooth-borne RPE group [5 males and 8 females, aged (10.1±1.0) years]. Ten sagittal linear indices [Y-Is distance (the distance from the incisor edge of the maxillary incisor to the vertical reference axis), Y-Ms distance (the distance from the mesial contact point of the maxillary first molar to the vertical reference axis), the relative distance between the maxillary and mandibular molars, overjet, etc.], 6 vertical linear indices [PP-Ms distance (the distance changes from Ms to the palatal plane), etc.] and 8 angle indices [SN-MP angle (the upper external angle of the intersection of the sella-nasion plane and the mandibular plane), U1-SN angle (the lower internal angle of the intersection of the long axis of the maxillary central incisor and the sella-nasion plane), etc.] were measured on the cephalometric radiographs before and after the treatment. Six coronal indicators (the inclination of the left and right first maxillary molar, etc.) were measured on cone-beam CT images before and after the treatment. The proportion of skeletal and dental factors in the changes of overjet were calculated. The differences of the index changes between groups were compared. Results: After the treatment, the anterior crossbite were corrected in both groups, and classⅠor classⅡ molar relationship were attained. In bone-anchored group, the changes of Y-Is distance, Y-Ms distance and maxillary and mandibular molar relative distance were (3.23±0.70), (1.25±0.34) and (2.54±0.59) mm, respectively, significantly less than those in the tooth-borned group in which the corresponding changes were (4.96±0.97) mm (t=-5.92, P<0.001), (3.12±0.83) mm (t=-7.53, P<0.001) and (4.92±1.35) mm (t=-5.85, P<0.05), respectively. The change of overjet in the bone-anchored group was (4.45±1.25) mm, significantly less than that in the tooth-borned group (6.14±1.29) mm (t=-3.38, P<0.05). Skeletal and dental factors accounted for 80% and 20% of the overjet changes in the bone-anchored group, respectively. While in the tooth-borned group, skeletal and dental factors accounted for 62% and 38% of the overjet changes, respectively. The PP-Ms distance change in the bone-anchored group [(-1.62±0.25) mm] was significantly less than that in the tooth-borned group [(2.13±0.86) mm] (t=-15.15, P<0.001). The changes of SN-MP and U1-SN in the bone-anchored group were -0.95°±0.55° and 1.28°±1.30°, respectively, significantly less than those corresponding indices in the tooth-borned group (1.92°±0.95°, t=-9.43, P<0.001; 7.78°±1.94°, t=-10.04, P<0.001). In the bone-anchored group, the inclination changes of maxillary bilateral first molars in the left and right sides were 1.50°±0.17° and 1.54°±0.19°, significantly less than the corresponding indices in the tooth-borned group (2.26°±0.37°, t=6.47, P<0.001; 2.25°±0.35°, t=6.81, P<0.001). Conclusions: The bone-anchored RPE with maxillary protraction could reduce the adverse tooth compensation effect, including the protrusion of maxillary anterior incisors, the increase of overjet and mandibular plane angle, and the mesial movement, extrusion and buccal inclination of maxillary molars.

[Fibrous hamartoma of infancy: a clinicopathological and molecular genetic analysis of 33 cases]

Objective: To investigate the clinicopathological features, immunophenotypic and molecular genetic characteristics and differential diagnosis of fibrous hamartoma of infancy (FHI). Methods: Thirty-three cases of surgically removed FHI were collected from the Department of Pathology, Henan Provincial People's Hospital from October 2011 to December 2020, the clinical and pathologic data with follow-up were collected and analyzed. Next-generation sequencing (NGS) and quantitative real time polymerase chain reaction (q-PCR) were used to study the molecular genetics. Results: The FHI cases occurred in 21 males and 12 females (mean age 16.7 months, range 6 months to 6 years). The sites included trunk (n=21), limb (n=11), and neck (n=1). All patients had painless solitary superficial soft tissue masses, the size was 1.5-9.0 cm (mean 3.8 cm). Microscopically, they were composed of mature adipose tissue, fibroblast/myofibroblast bundle and primitive mesenchymal cells in different proportions; giant cell fibroblastoma-like areas were seen in 14 cases. Immunohistochemistry showed variable expression of EGFR in the spindle cells and primitive mesenchymal components. In most cases, the spindle cells were positive for CD34 and SMA; giant cell fibroblastoma-like areas were strongly positive for CD34; and S-100 protein was expressed by adipocytes in all cases. Ki-67 labeling index ranged 1%-5%. There were recurrent somatic EGFR exon 20 insertion/duplication mutations in six cases tested by NGS, and there were three different mutation types: p.Asn771_His773dupAsnProHis, p.Pro772_His773insProProHis, and p.His773_Val774insThrHis. All the above 6 and another 15 tested cases showed EGFR exon 20 insertion/duplication mutations by q-PCR. Conclusions: FHI is a rare benign fibroblast/myofibroblast tumor. The characteristic histologic feature is organoid triphasic morphology, and the molecular feature is somatic mutation of EGFR exon 20 (insertion/duplication).

AB0506 PRELIMINARY STUDY ON IMBALANCE BETWEEN Th17 AND REGULATORY T CELLS IN ANTIPHOSPHOLIPID SYNDROME

Background

Antiphospholipid syndrome (APS) is a typical autoimmune disease, which can be classified into primary antiphospholipid syndrome (PAPS) and secondary antiphospholipid syndrome (SAPS) based on the presence or not of other autoimmune diseases. Disorders of peripheral blood lymphocyte and CD4+T cell subsets, especially Th17 and Treg cell subsets, may be involved in the pathogenesis of APS.

Objectives

To investigate the differences of peripheral blood lymphocyte and CD4+T cell subsets between patients with primary and secondary antiphospholipid syndrome and healthy controls, and to evaluate the correlation of antiphospholipid antibody titers and Th17/Treg values in PAPS and SAPS groups, as well as the correlation of cytokines and clinical characteristics in APS patients.

Methods

A total of 67 APS patients (12 PAPS patients, 55 SAPS patients) and 40 healthy controls were enrolled in this study. Retrospectively collected clinical and laboratory data of these patients. The absolute numbers of peripheral blood lymphocyte subsets and CD4+ T cell subsets were detected by flow cytometry, and serum cytokine levels were detected by flow cytometry bead array.

Results

Compared with healthy control group, the absolute values of T [689.26 vs. 1239.00, p＜0.001], B (104.69 vs. 177.50, p＜0.001), NK (98.97 vs. 300.00, p＜0.001) and CD4+T (330.16 vs. 628.50, p＜0.001) cells in SAPS group were decreased. While only the NK cells (151.30 vs. 300.00, p＝0.002) in the PAPS group were lower than that in healthy control group. However, the absolute values of T (1295.41 vs. 689.26, p＝0.001), B (184.44 vs. 104.69, p＝0.012), NK (151.30 vs. 98.97, p＝0.023) and CD4+T cells (698.34 vs. 330.16, p＝0.002) in PAPS group were significantly higher than those in SAPS group. For CD4+T cell subsets, PAPS patients and SAPS patients showed the same trend compared with healthy controls, showing increased Th1(111.50 vs. 23.47, p=0.002 and 71.43 vs. 23.47, p=0.001, respectively), decreased Th2(6.97vs.12.43, p=0.037 and 2.49 vs. 12.43, p＜0.001, respectively) and, more importantly, decreased Treg (18.77 vs. 29.53, p=0.031 and 12.01 vs. 29.53, p＜0.001, respectively), with increased Th17/Treg ratio (0.39 vs. 0.17, p=0.001 and 0.42 vs. 0.17, p＜0.001, respectively). Meanwhile, Th2(6.97 vs. 2.46, p＝0.006), Th17 (8.42 vs. 4.00, p＝0.042) and Treg (18.77 vs. 12.01, p＝0.020) cells in PAPS group were higher than those in SAPS group. As for the correlation study, we concluded that both aCL (r=0.6061, p=0.0405) and aβ2GPI (r=0.6900, p=0.0158) were positively correlated to Th17/Treg ratio in PAPS group. In addition, for APS patients, IL-2 (r=-0.420, p=0.010), IL-4 (r=-0.392, p=0.016), IL-10 (r=-0.331, p=-0.046), IL-17 (r=-0.479, p=0.006), and IFN-γ (r=-0.339, p=0.040) were negatively correlated with titers of aCL. And IL-6 is also associated with ESR (r=0.469, p=0.004) and CRP (r=0.670, p＜0.001).

Conclusion

Whether PAPS or SAPS patients, detection and balancing of lymphocyte and CD4+T subsets, especially Th17 and Treg subsets, may help correct immune disorders. Of course, the immune function of primary and secondary APS patients is not completely consistent, at least in terms of immune cells. Also, the role of cytokines in the pathogenesis of APS should not be ignored.

Figure 1.

Comparison of lymphocyte absolute values and CD4+ T cell subsets in PAPS group, SAPS group and healthy control group.

Figure 2.

The correlation analysis between the value of Th17/Treg and the titer of aCL and aβ2GPI in PAPS group and SAPS group, respectively.

Figure 3.

Heatmap of correlation of the serum cytokine levels of a variety of cytokines with clinical and laboratory characteristics of APS patients.

Disclosure of Interests

None declared

AB0269 THE CHARACTERISTICS OF PERIPHERAL LYMPHOCYTE SUBSETS AND CYTOKINES LEVEL IN RHEUMATOID ARTHRITIS WITH CORONARY ARTERY DISEASE

Background:

Rheumatoid arthritis (RA) is a systemic autoimmune disease. It is characterized by highly disabling polyarthritis, but extra-articular features are also common and portend a poor prognosis. Compared with the general population, the incidence and mortality of cardiovascular disease in RA are significantly increased. Chronic autoimmune inflammation is the common pathogenesis of RA and coronary heart disease(CAD). We’ve proved that lymphocyte subsets imbalance and high cytokines expression play an important role in the occurrence and development of RA diseases. However, the level of lymphocyte subsets and cytokines of RA patients with CAD are rarely reported[1-2].

Objectives:

To explore the clinical characteristic of lymphocyte subsets and cytokines of RA patients with CAD,and make comparisons with simple RA patients and healthy controls.

Methods:

The study included 96 patients with a diagnosis of RA according to the 1987 revised criteria of the ACR, including 54 RA patients with CAD and 42 RA patients without CAD and other cardiovascular disease, 40 healthy controls are also concluded. The absolute numbers of lymphocyte subsets and T subsets in peripheral blood were measured by Flow Cytometer (FCM). Serum levels of IL-2, IL-4, IL-6, IL-10, IL-17, INF-γ, and TNF-α were measured by flow microsphere capture chip technique (CBA) for 19 RA patients with CAD and 38 simple RA patients among 96 patients.We also collected relevant clinical information and made DAS28 score, and all patients are in the middle-high disease activity group (DAS28>3.2).

Results:

(1) There was no difference in DAS28 scores between the two groups(p=0.572). (2)Compared with RA patients without CAD, the absolute number of total T cell(P=0.035), total B cell (P=0.006), CD4+T cell(P=0.012), Th1 cell(P=0.037), Th17 cell(P=0.033) and CD4+CD25+FOXP3+ Treg(P=0.003) was lower than RA patients with CAD, the number of NK cell(P=0.685), CD8+T cell(P=0.322) and Th2 cell(P=0.770) had no obvious difference between them. (3)Compared with the healthy control, the absolute number of total T cell(P=0.014), total B cell (P=0.006), CD8+T cell(P=0.000) in RA with CAD was evidently lower, but there was no siginificant difference in absolute number of CD4+T cell(P=0.582), Th1 cell(P=0.052), Th2 cell(P=0.595), Th17 cell(P=0.148) and Treg(P=0.176) (Figure 1).(4) In RA patients with CAD,the level of cytokines IL-2(P=0.042), IL-4(P=0.043) and IL-17(P=0.012) was lower, while other cytokines had no difference (Table 1).

Figure 1.

The absolute number of lymphcytes of RA patients with CAD(n=54),RA patients without CAD (n=42) and healthy control (n=40). (*P<0.05,**P<0.01, ***P<0.001).

Table 1.

The expression level of cytokines of RA patients with CAD(n=19) and RA patients without CAD (n=38).

Cytokines (pg/ml)RA and CAD group(A) (n = 19)RA group(B) (n = 38)PvalueA vs. BIL-25.50(1.96, 12.82)6.82(4.45, 14.44)0.042IL-44.93(1.67, 9.41)6.28(4.49, 11.88)0.043IL-623.69(10.93, 73.08)36.67(15.40, 72.50)0.636IL-107.76(4.54, 10.50)7.62(5.69, 19.91)0.223IL-1710.81(4.04, 20.25)20.68(13.88, 45.58)0.012IFN-γ6.10(3.27, 13.84)7.13(5.79, 15.83)0.115TNF-α10.49(2.50, 29.04)14.96(10.03, 30.39)0.097

Conclusion:

Our research shows that there is lymphocyte imbalance and immune disorder existing in RA patients with CAD. Both the number of lymphocyte subsets and cytokine levels decreased in these patients than pure RA patients. It suggests that this group may be in lower immune state, which providing guidance for further clinical treatment of RA patients with CAD.

References:

[1]Winchester R, Giles JT, Nativ S, et al. Association of Elevations of Specific T Cell and Monocyte Subpopulations in Rheumatoid Arthritis With Subclinical Coronary Artery Atherosclerosis. [J]. Arthritis Rheumatol, 2016,68(1): 92-102.

[2]England BR, Thiele GM, Anderson DR, et al. Increased cardiovascular risk in rheumatoid arthritis: mechanisms and implications. [J]. BMJ, 2018 04 23;361.

Disclosure of Interests:

None declared

Changes in hippocampal ultrastructure and vimentin expression in rhesus monkeys following selective deep hypothermia and blood occlusion

Previous studies have shown that selective cerebral profound hypothermia combined with antegrade cerebral perfusion can improve resistance to cerebral hypoxia-ischemia in monkeys. The aim of this study was to observe the effect of selective cerebral profound hypothermia on the ultrastructure and vimentin expression in monkey hippocampi after severe cerebral ischemia. Eight healthy adult rhesus monkeys were randomly divided into two groups: profound hypothermia (N = 5) and normothermia (N = 3). Monkeys in the profound hypothermia group underwent bilateral carotid artery and jugular vein occlusion for 10 minutes at room temperature. Ringer's solution at 4°C was then perfused through the right internal carotid artery and out of the right jugular vein, maintaining the brain temperature below 18°C. Sixty minutes later, cerebral blood flow was restored. The normothermia group underwent all procedures with the exception that the Ringer's solution was 37°C during perfusion. All animals in the profound hypothermia group were successfully resuscitated. No significant abnormalities of hippocampal morphology or ultrastructure were observed. In contrast, no monkeys were alive after perfusion in the normothermia group and they had abnormal hippocampal morphology and ultrastructure to different extents. Vimentin expression in the hippocampus was significantly lower in the profound hypothermia group (47.88% ± 1.66) than the normothermia group (79.51% ± 1.00; P < 0.01). We conclude that selective cerebral profound hypothermia following 10-min occlusion of the bilateral common carotid arteries was able to downregulate vimentin expression in the hippocampus and protect it from severe cerebral ischemia.

The influencing factor of in vitro fertilization and embryonic transfer in the domestic fowl (Gallus domesticus)

This study was conducted to explore the influencing factors of ova in vitro fertilization (IVF) and transfer of the fertilized ova into the oviduct of recipient hens. The efficiency of fertilization was compared using three aspects: (i) the different time of ova collection and transfer, (ii) egg-laying period of recipient hen; and (iii) semen volume. The following results are observed: 72%, 40% and 0% of ova were found in ovarian sac in 30∼40 min, 50∼60 min and more than 90 min post-oviposition, respectively; 20%, 18%, 14% and 5.8% of ova were fertilized with 0.1, 0.2, 0.5 and 1.0 ml semen, respectively; and 33% and 100% of healthy chickens were hatched from fertile ova with 0.1 and 0.5 ml of semen, respectively. All oocytes obtained from ovary and mid-oviduct were unfertilized. Embryos were transferred into recipient hens 30 min ± 10 min post-oviposition, and 70% of shelled eggs were produced. There were no eggs produced in the other transfer times. This demonstrated that live chicken can be obtained by IVF of ova collected shortly after oviposition. It was important that the ovum was transferred into the oviduct infundibulum of recipient hens immediately or shortly after oviposition.

Directional differentiation of chicken primordial germ cells into adipocytes, neuron-like cells, and osteoblasts

Primordial germ cells (PGCs) are useful for producing transgenic chickens and preserving genetic material in avian species. In this study, we investigated the in vitro differentiation potential of chicken PGCs into different cell types. For differentiation into adipocytes, chicken PGCs were cultured for 21 days in induction media containing dexamethasone, insulin and/or 3-isobutyl-1-methylxanthine (IBMX), and differentiation rates ranging from 74% to 91% were identified by oil red-O and alkaline phosphatase (ALP) staining. For differentiation into neuron-like cells, chicken PGCs were cultured for 3 or 7 days in the induction media containing retinoic acid (RA) and IBMX, and differentiation rates ranging from 71% to 87% were identified by toluidine blue staining and immunohistochemical staining. For differentiation into osteoblasts, chicken PGCs were cultured for 15 or 21 days in the induction media containing desamethasone, beta-glycerol phosphate and/or vitamin C, and differentiation rates ranging from 47% to 79% were confirmed by Von Kossa, cytochemical and immunohistochemical staining. These data suggest that, like mammalian PGCs, chicken PGCs can differentiate into different cell types in vitro.

Gastric choriocarcinoma shows characteristics of adenocarcinoma and gestational choriocarcinoma: a comparative genomic hybridization and fluorescence in situ hybridization study

The authors report two cases of the rare primary gastric choriocarcinoma. These tumors showed an overwhelming predominance of cytotrophoblast- and syncytiotrophoblast-like tumor cells that were positive for beta-human chorionic gonadotrophin, with small foci of glandular differentiation. Beta-human chorionic gonadotrophin was also detected serologically in one patient. Comparative genomic hybridization study was performed on one specimen. Copy number gains of chromosomes 12, 17, 20, 22, and X, together with losses on 18q, were the major findings. Except for the gain of chromosome 12, which is known to be uncommon in primary gastric adenocarcinoma but frequently associated with choriocarcinoma, the remaining genomic imbalances were among the most common comparative genomic hybridization findings reported in primary gastric adenocarcinoma. Fluorescence in situ hybridization on paraffin sections of both specimens confirmed the presence of polysomy 17 and trisomy 12. These results suggest that primary gastric choriocarcinoma genetically possesses characteristics of both adenocarcinoma and gestational choriocarcinoma. The authors believe this is the first interphase cytogenetics study on this rare tumor, and that the results support the theory that gastric choriocarcinoma arises from alternate differentiation pathways of adenocarcinoma.

A role for HLA-DO as a co-chaperone of HLA-DM in peptide loading of MHC class II molecules

In B cells, the non-classical human leukocyte antigens HLA-DO (DO) and HLA-DM (DM) are residents of lysosome-like organelles where they form tight complexes. DM catalyzes the removal of invariant chain-derived CLIP peptides from classical major histocompatibility complex (MHC) class II molecules, chaperones them until peptides are available for loading, and functions as a peptide editor. Here we show that DO preferentially promotes loading of MHC class II molecules that are dependent on the chaperone activity of DM, and influences editing in a positive way for some peptides and negatively for others. In acidic compartments, DO is engaged in DR-DM-DO complexes whose physiological relevance is indicated by the observation that at lysosomal pH DM-DO stabilizes empty class II molecules more efficiently than DM alone. Moreover, expression of DO in a melanoma cell line favors loading of high-stability peptides. Thus, DO appears to act as a co-chaperone of DM, thereby controlling the quality of antigenic peptides to be presented on the cell surface.

Complete sequence analysis of the genome of the bacterium Mycoplasma pneumoniae

The entire genome of the bacterium Mycoplasma pneumoniae M129 has been sequenced. It has a size of 816,394 base pairs with an average G+C content of 40.0 mol%. We predict 677 open reading frames (ORFs) and 39 genes coding for various RNA species. Of the predicted ORFs, 75.9% showed significant similarity to genes/proteins of other organisms while only 9.9% did not reveal any significant similarity to gene sequences in databases. This permitted us tentatively to assign a functional classification to a large number of ORFs and to deduce the biochemical and physiological properties of this bacterium. The reduction of the genome size of M. pneumoniae during its reductive evolution from ancestral bacteria can be explained by the loss of complete anabolic (e.g. no amino acid synthesis) and metabolic pathways. Therefore, M. pneumoniae depends in nature on an obligate parasitic lifestyle which requires the provision of exogenous essential metabolites. All the major classes of cellular processes and metabolic pathways are briefly described. For a number of activities/functions present in M. pneumoniae according to experimental evidence, the corresponding genes could not be identified by similarity search. For instance we failed to identify genes/proteins involved in motility, chemotaxis and management of oxidative stress.

A novel method for efficient amplification of whole hepatitis B virus genomes permits rapid functional analysis and reveals deletion mutants in immunosuppressed patients

Current knowledge of hepatitis B virus (HBV) sequence heterogeneity is based mainly on sequencing of amplified subgenomic HBV fragments. Here, we describe a method which allows sensitive amplification and simplified functional analysis of full-length HBV genomes with or without prior cloning. By this method, a large number of HBV genomes were cloned from sera of six immunosuppressed kidney transplant patients. Two size classes of HBV genomes, one 3.2 kb and another about 2.0 kb in size, were found in all patients. The genome population from one serum sample was studied in detail by size analysis of subgenomic PCR fragments and sequencing. Regions with deletions and insertions were mapped in the C gene and pre-S region. Up to 100% of HBV genomes in all other immunosuppressed patients also had deletions in the C gene. Our results demonstrate the potential of the established method for the structural and functional characterization of heterogeneous populations of complete virion-encapsidated HBV DNAs and suggest that HBV genomes with C gene deletions can have a selective advantage in immunosuppressed patients.

[Internal iliac artery embolization for the control of severe bladder and prostate haemorrhage]

From 1986 to 1988, internal iliac artery embolization was used for the treatment of severe bladder or prostatic bleeding in 16 male patients with an age range of 44-72 years. Good and effective control of the bleeding was achieved in 15 patients without any complication. The experience about this technique was reported in this paper, and the indication and complication of the method were discussed. This method is simple, safe and effective in controlling massive bladder or prostate hemorrhage.