An antibody that prevents serpin polymerisation acts by inducing a novel allosteric behaviour.

Serpins are important regulators of proteolytic pathways with an anti-protease activity that involves a conformational transition from a metastable to a hyperstable state. Certain mutations permit the transition to occur in the absence of a protease; when associated with an inter-molecular interaction, this yields linear polymers of hyperstable serpin molecules, which accumulate at the site of synthesis. This is the basis of a number of pathologies termed the serpinopathies. We have previously identified a monoclonal antibody (mAb4B12) that, in single-chain form, blocks α1-antitrypsin (α1-AT) polymerisation in cells. Here we describe the structural basis for this activity. The mAb4B12 epitope was found to encompass residues Glu32, Glu39, and His43 on helix A and Leu306 on helix I. This is not a region typically associated with the serpin mechanism of conformational change, and correspondingly the epitope was present in all tested structural forms of the protein. Antibody binding rendered β-sheet A - on the opposite face of the molecule - more liable to adopt an 'open' state, mediated by changes distal to the breach region and proximal to helix F. The allosteric propagation of induced changes through the molecule was evidenced by an increased rate of peptide incorporation and destabilisation of pre-formed serpin-enzyme complex following mAb4B12 binding. These data suggest that prematurely shifting the β-sheet A equilibrium towards the 'open' state out of sequence with other changes suppresses polymer formation. This work identifies a region potentially exploitable for rational design of ligands that is able to dynamically influence α1-AT polymerisation

LAPORAN KKN REGULER 73 DIVISI II.D.2 ABEAN, AMBALKLIWONAN, AMBAL, KEBUMEN,

Di dusun Abean terjadi problematika yang berkaitan dengan bidang ekonomi dan juga pendidikan. Dalam bidang ekonomi, masyarakat sudah mampu memproduksi bahan mentah menjadi makanan, akan tetapi masyarakat mengalami beberapa kesulitan. Masyarakat kesulitan dalam hal pemasaran produk sehingga masyarakat belum mampu mengangkat dan mengembangkan produktifitas serta harga jual produk tersebut. Dalam bidang pendidikan, sebagian masyarakat hanya menempuh pendidikan sampai di tingkat Sekolah Menengah Pertama. Sedangkan dalam hal pendidikan non formal (TPA) dusun Abean belum terlaksana secara maksimal. Tujuan program Kuliah Kerja Nyata (KKN) Universitas Ahmad Dahlan (UAD) di dusun Abean mempunyai fokus pemberdayaan di bidang keagamaan, pendidikan, dan juga ekonomi. Dimana ketiga hal tersebut merupakan hal yang sangat mendasar untuk memberdayakan masyarakat yang nantinya akan bermanfaat baik dalam urusan keduniaan maupun yang berkaitan dengan sang Ilahi. Metode pelaksanaan yang dilakukan adalah dengan cara melakukan penyadaran agar masyarakat sadar akan potensi yang dimiliki dan pemdampingan untuk memaksimalkan potensi yang dimiliki. Diharapkan dengan adanya hal tersebut, mampu mengubah mindset masyarakat yang semula belum mempunyai keberanian untuk memasarkan potensi secara lebih luas. Selain itu, masyarakat bisa memajukan daerahnya sendiri, terutama memajukan dalam hal ekonomi masyarakat setempat

Cytotoxicity of leaves, stems, and flowers of Kecubung (Datura metel) extracts using the Brine Shrimp Lethality Test (BSLT) method

Brine shrimp (Artemia salina) cytotoxicity assays (BSLT) are one of the commonly used cytotoxic test methods to assess a plant extract's pharmacological activity and toxicity. Thus, this study aimed to examine the toxic levels of Kecubung (Datura metel) leaves extracted using different solvents, namely ethanol and ethyl acetate. The results showed that the LC50 value of flower ethanol, flower ethyl acetate, leaf ethanol, and stem ethyl acetate extracts had an LC50 value 1000, which was included in the toxic category. The LC50 value of flower ethanol is 121.044 ppm, flower ethyl acetate 105.89 ppm, leaf ethanol 639.589 ppm, and stem ethyl acetate 635.276 ppm. Ethanol leaf extract at a concentration of 1000 ppm showed the highest mortality with a percentage of 60% of the total number of A. salina. The flower ethanol extract showed the highest mortality at a concentration of 250 ppm with a percentage of 67% and at a concentration of 1000 ppm with a percentage of 70% of the total number of A. salina. Meanwhile, flower ethyl acetate and stem ethyl acetate extract at a concentration of 1000 ppm obtained 100% mortality of A. salina in the first 6 hours. The result shows that the flower ethyl acetate and stem ethyl acetate extract at a concentration of 1000 ppm is very toxic compared to other concentrations. Keywords: Toxicity Artemia salina LC50 Ethyl acetate Ethano

Strain-induced Evolution of Electronic Band Structures in a Twisted Graphene Bilayer

Here we study the evolution of local electronic properties of a twisted graphene bilayer induced by a strain and a high curvature. The strain and curvature strongly affect the local band structures of the twisted graphene bilayer; the energy difference of the two low-energy van Hove singularities decreases with increasing the lattice deformations and the states condensed into well-defined pseudo-Landau levels, which mimic the quantization of massive Dirac fermions in a magnetic field of about 100 T, along a graphene wrinkle. The joint effect of strain and out-of-plane distortion in the graphene wrinkle also results in a valley polarization with a significant gap, i.e., the eight-fold degenerate Landau level at the charge neutrality point is splitted into two four-fold degenerate quartets polarized on each layer. These results suggest that strained graphene bilayer could be an ideal platform to realize the high-temperature zero-field quantum valley Hall effect.Comment: 4 figure

Loss of LMOD1 impairs smooth muscle cytocontractility and causes megacystis microcolon intestinal hypoperistalsis syndrome in humans and mice

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a congenital visceral myopathy characterized by severe dilation of the urinary bladder and defective intestinal motility. The genetic basis of MMIHS has been ascribed to spontaneous and autosomal dominant mutations in actin gamma 2 (ACTG2), a smooth muscle contractile gene. However, evidence suggesting a recessive origin of the disease also exists. Using combined homozygosity mapping and whole exome sequencing, a genetically isolated family was found to carry a premature termination codon in Leiomodin1 (LMOD1), a gene preferentially expressed in vascular and visceral smooth muscle cells. Parents heterozygous for the mutation exhibited no abnormalities, but a child homozygous for the premature termination codon displayed symptoms consistent with MMIHS. We used CRISPR-Cas9 (CRISPR-associated protein) genome editing of Lmod1 to generate a similar premature termination codon. Mice homozygous for the mutation showed loss of LMOD1 protein and pathology consistent with MMIHS, including late gestation expansion of the bladder, hydronephrosis, and rapid demise after parturition. Loss of LMOD1 resulted in a reduction of filamentous actin, elongated cytoskeletal dense bodies, and impaired intestinal smooth muscle contractility. These results define LMOD1 as a disease gene for MMIHS and suggest its role in establishing normal smooth muscle cytoskeletal-contractile coupling

A systematic CRISPR screen defines mutational mechanisms underpinning signatures caused by replication errors and endogenous DNA damage

Mutational signatures are imprints of pathophysiological processes arising through tumorigenesis. We generated isogenic CRISPR-Cas9 knockouts (Δ) of 43 genes in human induced pluripotent stem cells, cultured them in the absence of added DNA damage, and performed whole-genome sequencing of 173 subclones. ΔOGG1, ΔUNG, ΔEXO1, ΔRNF168, ΔMLH1, ΔMSH2, ΔMSH6, ΔPMS1, and ΔPMS2 produced marked mutational signatures indicative of being critical mitigators of endogenous DNA modifications. Detailed analyses revealed mutational mechanistic insights, including how 8-oxo-dG elimination is sequence-context-specific while uracil clearance is sequence-context-independent. Mismatch repair (MMR) deficiency signatures are engendered by oxidative damage (C>A transversions), differential misincorporation by replicative polymerases (T>C and C>T transitions), and we propose a 'reverse template slippage' model for T>A transversions. ΔMLH1, ΔMSH6, and ΔMSH2 signatures were similar to each other but distinct from ΔPMS2. Finally, we developed a classifier, MMRDetect, where application to 7,695 WGS cancers showed enhanced detection of MMR-deficient tumors, with implications for responsiveness to immunotherapies

Differences in reproductive risk factors for breast cancer in middle-aged women in Marin County, California and a sociodemographically similar area of Northern California

<p>Abstract</p> <p>Background</p> <p>The Northern California county of Marin (MC) has historically had high breast cancer incidence rates. Because of MC's high socioeconomic status (SES) and racial homogeneity (non-Hispanic White), it has been difficult to assess whether these elevated rates result from a combination of established risk factors or other behavioral or environmental factors. This survey was designed to compare potential breast cancer risks and incidence rates for a sample of middle-aged MC women with those of a demographically similar population.</p> <p>Methods</p> <p>A random sample of 1500 middle-aged female members of a large Northern California health plan, half from Marin County (MC) and half from a comparison area in East/Central Contra Costa County (ECCC), were mailed a survey covering family history, reproductive history, use of oral contraceptives (OC) and hormone replacement therapy (HRT), behavioral health risks, recency of breast screening, and demographic characteristics. Weighted data were used to compare prevalence of individual breast cancer risk factors and Gail scores. Age-adjusted cumulative breast cancer incidence rates (2000–2004) were also calculated for female health plan members aged 40–64 residing in the two geographic areas.</p> <p>Results</p> <p>Survey response was 57.1% (n = 427) and 47.9% (n = 359) for MC and ECCC samples, respectively. Women in the two areas were similar in SES, race, obesity, exercise frequency, current smoking, ever use of OCs and HRT, age at onset of menarche, high mammography rates, family history of breast cancer, and Gail scores. However, MC women were significantly more likely than ECCC women to be former smokers (43.6% vs. 31.2%), have Ashkenazi Jewish heritage (12.8% vs. 7.1%), have no live births before age 30 (52.7% vs. 40.8%), and be nulliparous (29.2% vs. 15.4%), and less likely to never or rarely consume alcohol (34.4% vs. 41.9%). MC and ECCC women had comparable 2000–2004 invasive breast cancer incidence rates.</p> <p>Conclusion</p> <p>The effects of reproductive risks factors, Ashkenazi Jewish heritage, smoking history, and alcohol consumption with regard to breast cancer risk in Marin County should be further evaluated. When possible, future comparisons of breast cancer incidence rates between regions should adjust for differences in income and education in addition to age and race/ethnicity, preferably by using a sociodemographically similar comparison group.</p

CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

BACKGROUND: The antithyroid thioureylenes, propylthiouracil (PTU) and methimazole (MMI), are effective in the treatment of patients with plaque psoriasis. The mechanism of action of the drugs in psoriasis is unknown. Since the drugs reduce circulating IL-12 levels in patients with Graves' hyperthyroidism, the effect of propylthiouracil on CD1a expression in psoriatic lesions was examined in biopsy samples of patients with plaque psoriasis. CD1a is a marker of differentiated skin antigen presenting cells (APC, Langerhans cells). Langerhans cells and skin monocyte/macrophages are the source of IL-12, a key cytokine involved in the events that lead to formation of the psoriatic plaque. METHODS: Biopsy specimens were obtained from six patients with plaque psoriasis who were treated with 300 mg propylthiouracil (PTU) daily for three months. Clinical response to PTU as assessed by PASI scores, histological changes after treatment, and CD1a expression in lesional skin before and after treatment were studied. RESULTS: Despite significant improvement in clinical and histological parameters the expression of CD1a staining cells in the epidermis did not decline with propylthiouracil treatment. CONCLUSIONS: It appears that the beneficial effect of propylthiouracil in psoriasis is mediated by mechanisms other than by depletion of skin antigen-presenting cells