Stone weirs on Chipei Island, Taiwan--Landesque capital and ecologically unequal exchange

This thesis focuses on the development of stone weirs on Chipei Island. Chipei is one of the offshore islands of the Penghu archipelago in Taiwan. Stone weirs on Chipei Island have been in use for more than three centuries. The islanders developed a social structure based on building and utilizing stone weirs for fishing. Stone weirs are central to the legacies of every family on Chipei. Nowadays, most people still hold shares in stone weirs. The development of stone weirs on Chipei Island is examined from the perspective of historical-political ecology, more specifically drawing on the concepts of landesque capital and ecologically unequal exchange. Three phases were carried out in the use of stone weirs, 1) pre-1940s, stone weir as landesque capital, when the KMT took over 2) from the end of the 1940s to the 1970s ecologically unequal exchange occurred in the stone weirs and Chipei Island 3) from post-1970s, tourist industry became the most important sector that stone weirs become a destination of tourists

Decreased MicroRNA-221 is Associated with High Levels of TNF-a in Human Adipose Tissue-Derived Mesenchymal Stem Cells From Obese Woman

Aim: The present study aimed to investigate the regulation and involvement of miR-221 in the differentiation of human adipose tissue-derived mesenchymal stem cells (hASCs). The relationships between miR-221 and pro-inflammatory markers and adipokines were also explored. Methods: Eight adipose tissues were obtained from four obese (mean body mass index (BMI) =31.7 kg/m2) and four lean (mean BMI= 21.5 kg/m2) women. hASCs were induced to differentiate, and the related gene expression were measured in the hASC-differentiated adipocytes using real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR). Results: During adipogenesis, miR-221 was significantly down-regulated; furthermore, miR-221 levels were lower in hASC-differentiated adipocytes from obese subjects than in the corresponding adipocytes from lean subjects. Higher TNF-α mRNA levels were associated with lower levels of miR-221. In addition, the miR-221 levels in the adipocytes were inversely correlated with BMI. Conclusion: Our results support the link between miR-221 and obesity development as well as obesity related inflammatory status

HSPB7 prevents cardiac conduction system defect through maintaining intercalated disc integrity

<div><p>HSPB7 is a member of the small heat-shock protein (HSPB) family and is expressed in the cardiomyocytes from cardiogenesis onwards. A dramatic increase in HSPB7 is detected in the heart and blood plasma immediately after myocardial infarction. Additionally, several single-nucleotide polymorphisms of HSPB7 have been identified to be associated with heart failure caused by cardiomyopathy in human patients. Although a recent study has shown that HSPB7 is required for maintaining myofiber structure in skeletal muscle, its molecular and physiological functions in the heart remain unclear. In the present study, we generated a cardiac-specific inducible HSPB7 knockout mouse and demonstrated that the loss of HSPB7 in cardiomyocytes results in rapid heart failure and sudden death. The electrocardiogram showed cardiac arrhythmia with abnormal conduction in the HSPB7 mutant mice before death. In HSPB7 CKO cardiomyocytes, no significant defect was detected in the organization of contractile proteins in sarcomeres, but a severe structural disruption was observed in the intercalated discs. The expression of connexin 43, a gap-junction protein located at the intercalated discs, was downregulated in HSPB7 knockout cardiomyocytes. Mislocalization of desmoplakin, and N-cadherin, the intercalated disc proteins, was also observed in the HSPB7 CKO hearts. Furthermore, filamin C, the interaction protein of HSPB7, was upregulated and aggregated in HSPB7 mutant cardiomyocytes. In conclusion, our findings characterize HSPB7 as an intercalated disc protein and suggest it has an essential role in maintaining intercalated disc integrity and conduction function in the adult heart.</p></div

Loss of HSPB7 results in FLNC protein upregulation and aggregation.

<p>Confocal micrographs of longitudinal sections (A) and cross-sections (B) of the heart. FLNC aggregation (arrowheads) was observed only in the mutant cardiomyocytes. Extracellular matrix accumulation was labeled using wheat germ agglutinin (WGA). The nucleus was visualized through Hoechst 33342 staining. Scale bar: 50 μm. (C) Immunoblot analysis and quantitation (D) of the expression levels of FLNC in the cardiac muscle. The muscle homogenate supernatant (S) and pellet (P) fractions were analyzed from control and CKO mice at d7 after tamoxifen administration. GAPDH and Coomassie Blue staining were used to verify the loading amount in the supernatant and pellet. n = 3 per group. Data are presented as means ± SD. *, <i>P</i> < 0.05 relative to the control.</p

Expression and localization of HSPB7 in cardiac muscle.

<p>(A) Immunoblot analysis of the cardiac muscle showing HSPB7 constitutive expression from the embryonic stages to adulthood (E14.5 to P28) with multiple forms of HSPB7 at different molecular masses (arrows). (B) Subcellular localization of HSPB7 in the cardiac muscle of adult mice. The heart sections were stained with antibodies against HSPB7 (red) and desmoplakin (desmosome), α-actinin (Z-line), myomesin (M-line), N-cadherin (adhering junction), connexin 43 (gap junction), and cardiac-actin (I-bend). HSPB7 mainly localizes at the intercalated discs and is adjacent to the Z-line with a striated pattern. (C) Colocalization of HSPB7 with N-cadherin during development. Heart sections from the embryonic stages to adulthood (E14.5 to P56) were stained with antibodies against HSPB7 (red) and N-cadherin (green). The nucleus was visualized through Hoechst 33342 staining. Insets show the representative areas with higher magnification. Scale bar: 10 μm.</p

Electrical conduction is impaired in HSPB7 CKO hearts.

<p>(A and B) Annotated ECG curve of the HSPB7 CKO and control animals before (A) and 7 days after (B) the first tamoxifen injection. (C and D) Quantification of the ECG changes in HSPB7 CKO and control animals before (C) and 7 days after (D) the first tamoxifen administration. N = 5 per group. Data are presented as means ± SD. *, <i>P</i> < 0.05 **, <i>P</i> < 0.01 relative to the control. (E) Representative telemetric 2-lead ECG recording of a tamoxifen-treated HSPB7 CKO and control mice. Telemetry ECG recordings of lethal arrhythmias in HSPB7 CKO mice. n = 2 per group.</p

Expression and localization of ID complex proteins in HSPB7 CKO hearts.

<p>(A) Confocal micrographs of longitudinal sections of the cardiac muscle of control and CKO mice at d7 after tamoxifen administration. Specific antibodies were used to identify the distributions of intercalated disc components: N-cadherin, desmoplakin, vinculin, and connexin 43. In HSPB7 CKO hearts, the staining of desmoplakin and N-cadherin were distributed throughout the cytoplasm, but little was observed in control hearts. Connexin 43 was absent from the intercalated discs in HSPB7 CKO hearts. The insets show representative areas at a higher magnification. The nucleus was visualized through Hoechst 33342 staining. n = 4 per group. Scale bar: 20 μm. (B) Immunoblotting of intercalated discs and sarcomeric-associated proteins in HSPB7 CKO and control hearts. GAPDH signal shows the loading of the samples between the lanes. n = 4 per group. (C) Quantitative analysis of immunoblot analysis of protein levels in cardiac tissue from control and CKO mice. Seven days after the first tamoxifen injections, connexin 43 protein expression dropped to < 40% in CKO animals, as determined by immunoblot analysis. Data are presented as means ± SD. *, <i>P</i> < 0.05, **, <i>P</i> < 0.01 relative to control.</p

Characterization of HSPB7 CKO mouse.

<p>(A) Immunoblot analysis for HSPB7 protein expression levels in control (Flox/Flox) and CKO animals 4 days (d4) and 7 days (d7) after tamoxifen administration. The GAPDH signal shows the loading of samples between lanes. (B) Quantitative analysis for immunoblot analysis of HSPB7 expression protein levels in cardiac tissue from control and CKO mice. Seven days after the first tamoxifen administration, HSPB7 protein expression dropped to less than 10% in CKO animals, as determined by immunoblot blot (HSPB7 compared with GAPDH). Data are presented as means ± SD. (C) Double staining of the left ventricle section with HSPB7 and Hoechst 33342 in the control and CKO hearts at d7 after tamoxifen administration. HSPB7 was no longer present at the intercalated disc and sarcomere. Scale bar: 20 μm (D) Significant increase in heart weight in HSPB7 CKO mice (n = 8; *<i>p</i> = 0.00027). (E) Kaplan–Meier survival curve of HSPB7 CKO and control mice. (F) Representative whole mounts (left), Masson’s trichrome (middle left and right), and hematoxylin-eosin–stained (right) transverse sections of control and CKO mouse hearts. Histological analysis showed inflammatory infiltration in the myocardium, identified as mostly lymphocytes and plasma cells, in HSPB7 CKO hearts at d7 after tamoxifen administration. In addition, Masson’s trichrome staining showed no significant collagen deposition in HSPB7 CKO hearts, as compared to control mice.</p

Intramyocardial injection with Adeno-Cre in HSPB7^Flox/Flox mice.

<p>Confocal micrographs of the cardiac muscle of the HSPB7^Flox/Flox mice 8 days after intramyocardial injection with Adeno-Cre virus. n = 3 per group. The heart sections were co-immunostained with antibody against HSPB7 (red) and specific antibodies (green) were used to identify the distributions of intercalated disc components: desmoplakin (A) and N-cadherin (B). (A) In HSPB7^Flox/Flox hearts, desmoplakin was distributed throughout the cytoplasm (asterisk in lower panel) at the HSPB7 depleted region compared with the control region (upper panel). (B) N-cadherin exhibited partial misexpression at the HSPB7 depleted region (asterisk in lower panel) compared with the control region (upper panel). The nucleus was visualized through Hoechst 33342 staining (blue). Scale bar: 10 μm.</p