Implantation of bone marrow mononuclear cells using injectable fibrin matrix enhances neovascularization in infarcted myocardium

Neovascularization may improve cardiac function and prevent further scar tissue formation in infarcted myocardium. A number of studies have demonstrated that bone marrow-derived cells have the potential to induce neovascularization in ischemic tissues. In this study, we hypothesized that implantation of bone marrow mononuclear cells (BMMNCs) using injectable fibrin matrix further enhances neovascularization in infarcted myocardium compared to BMMNC implantation without matrix. To test this hypothesis, infarction was induced in rat myocardium by cryoinjury. Three weeks later, rat BMMNCs were mixed with fibrin matrix and injected into the infarcted myocardium. Injection of either BMMNCs or medium alone into infarcted myocardium served as controls. Eight weeks after the treatments, histological analyses indicated that implantation of BMMNCs using fibrin matrix resulted in more extensive tissue regeneration in the infarcted myocardium compared to BMMNC implantation without matrix. Examination with fluorescence microscopy revealed that cells labeled with a fluorescent dye prior to implantation survived in the infarcted myocardium at 8 weeks of implantation. Importantly, implantation of BMMNCs using fibrin matrix resulted in much more extensive neovascularization in infarcted myocardium than BMMNC implantation without matrix. The microvessel density in infarcted myocardium was significantly higher (p < 0.05) when BMMNCs were implanted using fibrin matrix (350 +/- 22 microvessels/mm2) compared to BMMNC implantation without matrix (262 +/- 13 microvessels/mm2) and medium injection (76 +/- 9 microvessels/mm2). In addition, average internal diameter of microvessels was significantly larger (p < 0.05) in BMMNC implantation with fibrin matrix group (14.6 +/- 1.2 microm) than BMMNC implantation without matrix group (10.2 +/- 0.7 microm) and medium injection group (7.3 +/- 0.5 microm). These results suggest that fibrin matrix could serve as a cell implantation matrix that enhances neovascularization efficacy for myocardial infarction treatment.     

Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes

The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.      

Desmoplastic small round cell tumor presenting as a neck mass: a case report

An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized.     

Progression of meiotic DNA replication is modulated by interchromosomal interaction proteins, negatively by Spo11p and positively by Rec8p

Spo11p is a key mediator of interhomolog interactions during meiosis. Deletion of the SPO11 gene decreases the length of S phase by approximately 25%. Rec8p is a key coordinator of meiotic interhomolog and intersister interactions. Deletion of the REC8 gene increases S-phase length, by approximately 10% in wild-type and approximately 30% in a spo11Delta background. Thus, the progression of DNA replication is modulated by interchromosomal interaction proteins. The spo11-Y135F DSB (double strand break) catalysis-defective mutant is normal for S-phase modulation and DSB-independent homolog pairing but is defective for later events, formation of DSBs, and synaptonemal complexes. Thus, earlier and later functions of Spo11 are defined. We propose that meiotic S-phase progression is linked directly to development of specific chromosomal features required for meiotic interhomolog interactions and that this feedback process is built upon a more fundamental mechanism, common to all cell types, by which S-phase progression is coupled to development of nascent intersister connections and/or related aspects of chromosome morphogenesis. Roles for Rec8 and/or Spo11 in progression through other stages of meiosis are also revealed.     

Comparison of full length sequences of hepatitis B virus isolates in hepatocellular carcinoma patients and asymptomatic carriers of Korea

Relatively few genomic sequences of Korean hepatitis B virus (HBV) isolates are available. Moreover, no comparative study has been made between the full-length genomes of Korean HBV isolates and clinical status. To evaluate mutations in HBV isolates obtained from chronically infected HBV patients in terms of clinical significance, we determined the genomic sequences of HBV isolates obtained from three hepatocellular carcinoma (HCC) patients (He52, He53, and He82) and from three asymptomatic carriers (He74, He100, and He127). A comparison of sequence variations showed that the HBV isolates from the three HCC patients showed higher frequencies of mutation than the isolates from the three asymptomatic carriers. Three characteristic mutation patterns were identified in the HBV isolates from the HCC patients, which distinguished the HBV isolates from the asymptomatic carriers. First, HBV isolates from the three HCC patients both had double mutations in a core promoter (T1762/A1764) and a precore mutation (A1896). Second, although these isolates belonged to genotype C, 11 amino acids deletions in the preS1 region, specific for HBV genotype D, were detected in the isolates of two HCC patients (He52 and He82). Third, mutations (I127T/N, K130M, and V131I) at three codons in the carboxy functional region of X protein were observed in isolates from all three HCC patients. Additionally, phylogenetic analysis based on the entire HBV sequences showed that all six isolates belonged to genotype C2, as do other Korean strains.     

Cell death in retinoblastoma: electron microscopic, immunohistochemical, and DNA fragmentation studies

Apparent cell loss by apoptosis occurs in carcinomatous tissue. To investigate cell death in retinoblastoma (Rb), ultrastructural examination, ApopTag staining, electrophoresis to detect apoptotic DNA fragmentation, and flow cytometric studies were performed. Immunostaining for the oncogenic products bcl-2 and p53 was also carried out. Relationships between the proliferation fraction (PF), apoptotic index (AI), and the distribution of bcl-2 and p53 were investigated according to the degree of histologic differentiation of Rb. Ultrastructurally, two patterns of cell death were seen. Necrotic cells exhibited vacuolation of cytoplasmic organelles with a marked lytic change in the karyoplasm and cytoplasm. In contrast, apoptotic cells were characterized by crescentic margination of chromatin, condensation of karyoplasm and cytoplasm, and fragmentation of the nucleus. Differentiated Rb had a low AI value (< 1%), whereas undifferentiated Rb had a high AI value (> 8%). The PF of undifferentiated RB (31%) was significantly higher than that of differentiated RB (14%). Analysis of DNA fragmentation using 3'-end labeling with terminal transferase indicated that undifferentiated Rb has increased DNA cleavage. The distribution of apoptotic bodies within Rb was inversely correlated with the expression of bcl-2. A majority of tumor cells of differentiated Rb were negative for p53, whereas 20-40% of tumor cells of undifferentiated Rb showed a positive reaction for p53. These findings suggest that the degree of susceptibility to apoptosis is closely related to PF, is inversely related to the degree of differentiation of Rb, and is protected by oncogene bcl-2.     

Family Belongingness Attenuates Entrapment and Buffers Its Association with Suicidal Ideation in a Sample of Dutch Sexual Minority Emerging Adults

Sexual minority emerging adults are more likely to engage in suicidal ideation than their heterosexual counterparts. Experiences of homophobic violence are associated with suicidal ideation. Yet, the specific mechanisms linking homophobic violence to suicidal ideation remain unclear. Entrapment and social belongingness were tested to determine their relevance for understanding the link between homophobic violence and suicidal ideation. A sample of sexual minority Dutch emerging adults (N?=?675; ages 18–29, M?=?21.93 years, SD?=?3.20) were recruited through online platforms and flyers. Homophobic violence was expected to be positively associated with suicidal ideation and entrapment. The association between homophobic violence and suicidal ideation was expected to be indirectly linked through entrapment. We explored whether various sources of social belongingness moderated the path between entrapment and suicidal ideation and whether those sources of social belongingness moderated the indirect effect of homophobic violence on suicidal ideation through entrapment. Results showed that homophobic violence and entrapment were positively associated with suicidal ideation and that family belongingness was negatively associated with suicidal ideation. Homophobic violence and suicidal ideation were not indirectly linked through entrapment. The interaction effect between entrapment and family belongingness was significant, suggesting that, on average, the effect of entrapment on suicidal ideation decreased when family belongingness was high. These results suggest that family belongingness may reduce the association between entrapment and suicidal ideation while adjusting for homophonic violence. Reducing entrapment and improving family belongingness may be useful targets for programs aimed at preventing suicidal ideation among sexual minority emerging adults.

     

合心爽,硝酸甘油治疗不稳定型心绞痛对比研究

目的 比较用硝酸甘油和合心爽治疗９８例不稳定型心绞痛的疗效。方法 随机分组,分别静滴合心爽和硝酸甘油,以难治性心绞痛、心肌梗塞或缺血性猝死为治疗终点。结果 发展为难治性心绞痛或心肌梗塞病例在合心爽组为５人,硝酸甘油组为１１人,发生心肌梗塞者合心爽组３人,硝酸甘油８人,缺血性猝死者合合爽组无,硝酸甘油组１人。结论 静脉用合心爽治疗不稳定型心绞痛疗效优于硝酸甘油（Ｐ〈０．００１）。     

Intranuclear inclusions in subtypes of striatal neurons in Huntington's disease transgenic mice

R6/2 transgenic mice express exon 1 of an abnormal human Huntington's disease (HD) gene and develop a neurological phenotype similar to HD. These mice develop ubiquitinated neuronal intranuclear inclusions (NII) which might play a central role in the pathophysiology of HD. We studied the distribution of NII in subpopulations of striatal neurons in 12-week-old R6/2 transgenic mice using fluorescent double label immunohistochemistry. We observed that most of the Calbindin-D28K positive projection neurons (89%) and the Parvalbumin positive interneurons (86%) showed ubiquitinated NII. In interneurons, however, which contain either choline acetyltransferase, neuronal nitric oxide synthase, or Calretinin, the frequency of NII was much lower (22%, 8%, 9%, respectively). Our data suggest that subpopulations of striatal neurons differ remarkably in their capability of forming ubiquitinated NII. Interneurons which are known to resist neurodegeneration in HD show less NII.