A metabolic-dysfunction associated steatotic liver acinus biomimetic induces pancreatic islet dysfunction in a coupled microphysiology system

Preclinical and clinical studies suggest that lipid-induced hepatic insulin resistance is a primary defect that predisposes to dysfunction in pancreatic islets, implicating a perturbed liver-pancreas axis underlying the comorbidity of T2DM and MASLD. To investigate this hypothesis, we developed a human biomimetic microphysiological system (MPS) coupling our vascularized liver acinus MPS (vLAMPS) with primary islets on a chip (PANIS) enabling MASLD progression and islet dysfunction to be quantitatively assessed. The modular design of this system (vLAMPS-PANIS) allows intra-organ and inter-organ dysregulation to be deconvoluted. When compared to normal fasting (NF) conditions, under early metabolic syndrome (EMS) conditions, the standalone vLAMPS exhibited characteristics of early stage MASLD, while no significant differences were observed in the standalone PANIS. In contrast, with EMS, the coupled vLAMPS-PANIS exhibited a perturbed islet-specific secretome and a significantly dysregulated glucose stimulated insulin secretion (GSIS) response implicating direct signaling from the dysregulated liver acinus to the islets. Correlations between several pairs of a vLAMPS-derived and a PANIS-derived secreted factors were significantly altered under EMS, as compared to NF conditions, mechanistically connecting MASLD and T2DM associated hepatic factors with islet-derived GLP-1 synthesis and regulation. Since vLAMPS-PANIS is compatible with patient-specific iPSCs, this platform represents an important step towards addressing patient heterogeneity, identifying complex disease mechanisms, and advancing precision medicine.

A rare case of colonic diverticulum in a Bitch

Abstract.

Background

Colonic diverticulum is one of the rare findings in dogs characterized by an out-pouching of mucosal and submucosal layers through the defect in muscularis layer of the colon.

Case description

A five years old intact female Labrador was presented with an anamnesis of dyschezia and tenesmus.

Findings/treatment and outcome

Rectal examination was normal, and the survey radiograph showed an almost crescent shaped abnormal dilatation (10.52 cm × 6.21 cm) with gas and increased radiopaque material, dorsal to the urinary bladder and ventral to the descending colon suggesting fecal stasis. Ultrasonographic examination revealed gas-filled out-pouching with hyperechoic colon wall and acoustic shadowing. Exploratory celiotomy confirmed the diagnosis of colonic diverticulum, and diverticulectomy was performed. All four layers of the colonic wall were detected histopathologically in the biopsy sample and excluded neoplasia. The dog recovered uneventfully with no post-operative complications.

Conclusion

This surgery produced an excellent resolution of clinical signs. To our knowledge, this is one of the few cases of colonic diverticulum reported in dogs.

Dexmedetomidine as an adjuvant to 0.25% bupivacaine in ultrasound guided femoral nerve block for preoperative positioning and postoperative analgesia in patients undergoing elective surgery for fracture shaft of femur

Background:

Femur fracture causes excruciating pain and surgical repair is recommended. To obtain satisfactory patient co-operation in the perioperative period, various analgesics have been used. Femoral nerve block (FNB) provides an excellent alternative for analgesia in the perioperative period. Dexmedetomidine of up to 2 μg.kg⁻¹ has been used in FNB as adjuvants in lower limb surgeries.

Aims:

The aim was to study the effect of addition of Dexmedetomidine to Bupivacaine in FNB on the comfort of positioning for subarachnoid block (SAB) and postoperative analgesia.

Materials and Methods:

Prospective, randomized, double-blind design was followed. Seventy American Society of Anesthesiologist I and II patients aged 18–70 years of either gender were randomly allocated into Group B (20 mL 0.25% Bupivacaine + 2 mL Normal Saline) and Group BD (received 20 mL 0.25% Bupivacaine + Dexmedetomidine 2 μg.kg⁻¹ diluted to 2 mL) for FNB. Numerical rating scale (NRS) was recorded before and after FNB and comfort of positioning graded. After 10 min, subarachnoid block (SAB) was administered. NRS was recorded postoperatively until 24 h.

Results:

The comfort of positioning improved in both the groups after FNB but was statistically not significant when compared among the groups (P = 0.7). Duration of postoperative analgesia was significantly higher in the Group BD (741 min ± 97 min) compared to the Group B (440 min ± 45 min) (P = 0.001) and was statistically significant.

Conclusion:

FNB improved the comfort of positioning for SAB, but the addition of Dexmedetomidine did not have any added advantages with respect to comfort of positioning. However, the addition of Dexmedetomidine significantly increased the duration of postoperative analgesia with minimal hemodynamic changes.

Noticeable improvement in the toxic gas-sensing activity of the Zn-doped TiO2 films for sensing devices

Sensing element view, sening mechanism, stability, response and recovery time of the Zn-doped TiO₂ films.

Engineered peptide modified hydrogel platform for propagation of human pluripotent stem cells

Human pluripotent stem cells (hPSCs) have enormous potential to alleviate cell needs for regenerative medicine, however these cells require expansion in cell colonies to maintain cell-cell contact, thus limiting the scalability needed to meet the demands of cell therapy. While the use of a Rho-associated protein kinase (ROCK) inhibitor will allow for culture of single cell hPSCs, typically only 50% of cells are recovered after dissociation. When hPSCs lose cell-cell contact through E-cadherin, dissociation induced apoptosis occurs. In this study, we hypothesized that the extracellular E-cadherin domain of hPSCs will bind to synthetic E-cadherin peptides presented on a hydrogel substrate, mimicking the required cell-cell contact and thereby retaining single-cell viability and clonogenicity. Hence, the objective of this study was to functionalize alginate hydrogels with synthetic peptides mimicking E-cadherin and evaluate peptide performance in promoting cell attachment, viability, maintaining pluripotency, and differentiation potential. We observed that alginate conjugated with synthetic E-cadherin peptides not only supported initial cell attachment with high viability, but also supported hPSC propagation and high fold expansion. hPSCs propagated on the peptide modified substrates maintained the hPSC characteristic pluripotency and differentiation potential, characterized by both spontaneous and directed differentiation. STATEMENT OF SIGNIFICANCE: Human pluripotent stem cells (hPSCs) have enormous potential to alleviate cell needs for regenerative medicine and cell therapy. However, scalable culture of hPSCs is challenged by its need for maintenance of cell-cell contact, dissociation of which triggers the apoptotic pathway. Hence hPSCs are commonly maintained as colonies over Matrigel coated culture plates. Furthermore, use of xenogenic and undefined Matrigel compromises the translational potential of hPSCs. In this work we have developed a completely defined substrate to enable adherent culture of hPSCs as single cells. This substrate prevents apoptosis of the single cells and allows significant fold expansion of hPSCs while maintaining pluripotency and differentiation potential. The developed substrate is expected to be a cost-effective and translatable alternative to Matrigel.

Inducing apatite pre-layer on titanium surface through hydrothermal processing for osseointegration

Commercially available titanium (Ti) having high mechanical strength and a low area of cross-section can be adequately exploited for minimally invasive dental implantation. Current directions in clinical dental implant therapy focus on endosseous dental implant surfaces with nanoscale topographies using easy and economical processing approaches. The present study describes the generation of a novel nanolayer nucleating agent on the surface of Ti implant for early endosseous after implantation. The strategy is to modify the surface of Ti implant using Ca(OH)₂ via hydrothermal technique (Ti-HT). The X-ray photoelectron spectroscopy analysis confirmed the presence of chemically bonded Ca ions on the Ti surface in the form of CaTiO₃. In vitro studies are carried out to confirm the bone bonding ability of calcium enriched Ti surface. The apatite deposition on the surface after exposure to SBF for 7 days is confirmed via scanning electron microscopy, X-ray powder diffraction, Fourier-transform infrared spectroscopy and energy-dispersive X-ray spectroscopy techniques. The cell viability of Ti-HT was evaluated using direct contact method and MTT assay. The potential of Ca²⁺ ion on Ti surface via hydrothermal pre-treatment to enhance osseointegration of Ti has been proposed for achieving early stability for dental implants.

Effect of obturating materials on fracture resistance of simulated immature teeth

Aim:

The aim of this study was to evaluate the fracture resistance of simulated immature teeth, when the root canals were completely filled either with mineral trioxide aggregate (MTA) or Biodentine, comparing with that of roots filled with apexification procedure.

Materials and Methods:

Sixty mandibular premolar teeth with single, straight canals decoronated at cementoenamel junction were divided into five groups (n = 12 each). Group 1 samples served as negative control and remaining four groups root samples were shaped and cleaned using ProTaper rotary files. To simulate immature roots, a #5 Peeso reamer was passed beyond the apex so that apices were enlarged to a diameter of 1.5 mm. Group 2 and 4 samples were filled with 5 mm of MTA or Biodentine apical plug and backfilling with gutta-percha using AH Plus sealer. Group 3 and 5 root samples were completely obturated with MTA and Biodentine, respectively. All the teeth were loaded vertically until fracture, using the universal testing machine.

Statistical Analysis:

Forces at which fracture of the roots occurred were subjected to statistical analysis using SPSS/PC version 2 software, and the results were analyzed with the one-way analysis of variance and Newman–Keuls multiple post hoc test.

Results:

Complete root canal obturation with MTA or Biodentine has shown significantly higher fracture resistance (P < 0.05) when compared to apexification with MTA or Biodentine.

Conclusion:

Obturation of the root canals with bioactive materials has shown highest fracture resistance when compared to apexification groups.

Tosylate salts of the anticancer drug lapatinib

Two tosylate salts of an anticancer drug lapatinib, viz. a monotosylate [systematic name: ({5-[4-({3-chloro-4-[(3-fluorophenyl)methoxy]phenyl}amino)quinazolin-6-yl]furan-2-yl}methyl)[2-(methylsulfonyl)ethyl]azanium 4-methylbenzenesulfonate], C29H27ClFN4O4S(+)·C7H7O3S(-), (I), and a ditosylate [systematic name: 4-({3-chloro-4-[(3-fluorophenyl)methoxy]phenyl}amino)-6-]5-({[2-(methylsulfonyl)ethyl]azaniumyl}methyl)furan-2-yl[quinazolin-1-ium bis(4-methylbenzenesulfonate)], C29H28ClFN4O4S(2+)·2C7H7O3S(-), (II), were obtained during crystallization attempts for polymorphism. In both structures, the lapatinib cation is in a distorted U-like conformation and the tosylate anion is clamped between the aniline N atom and methylamine N atom through N-H···O hydrogen bonds, forming an R2(2)(15) ring motif. The 4-anilinoquinazoline ring system is essentially planar in (I), while it is twisted in (II), controlled by an intramolecular C-H···N interaction. In (I), alternating cations and anions are linked by N-H···O hydrogen bonds into C2(2)(6) chains. These chains are linked by cations in a helical manner. The presence of the additional tosylate anion in (II) results in the formation of one-dimensional tapes of fused hydrogen-bonded rings through N-H···O and C-H···O interactions. These studies augment our understanding of the role of nonbonded interactions in the solid state, which is useful for correlation to the physicochemical properties of drug products.

2-[(Ferrocen-1-yl)(hydroxy)methyl]prop-2-enenitrile

In the title ferrocene derivative, [Fe(C5H5)(C9H8NO)], the dihedral angle between the enenitrile group and the substituted cyclopentadienyl ring is 71.2 (1)°. The cyclopentadienyl rings of the ferrocene moiety are arranged in an eclipsed conformation. The hydroxy group, and the corresponding methine H atom, are disordered over two sets of sites with site-occupancy factors of 0.744 (4) and 0.256 (4). An intramolecular C—H...O close contact is observed. In the crystal, O—H...N hydrogen bonds form aC(6) chain along [100].

Synthesis, structural elucidation and spectroscopic analysis of 3a,8b-dihydroxy-4-oxo-1H,2H,3H,3aH,4H,8bH-indeno[1,2-d]imidazolidin-2-iminium chloride

Ninhydrin guanidinium chloride (3a,8b-dihydroxy-4-oxo-1H,2H,3H,3aH,4H,8bH-indeno [1,2-d]imidazolidin-2-iminium chloride) a semiorganic crystal was synthesized. The structure was determined using X-ray single crystal technique. Comparisons between the FT-IR spectrum of ninhydrin guanidinium chloride with ninhydrin were made. Melting point was found using thermal measurements. The molecular geometry, vibrational frequencies and Mulliken charges of the compound in the ground state have been calculated by the density functional theory (DFT) method with 3-21G(d,p) basis set and theoretical frequencies were compared with the experimental FT-IR spectrum. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis, natural bond orbitals (NBO) and thermodynamic properties at various temperatures of the compound were investigated by theoretical calculations.

4-[(E)-(Hydroxyimino)methyl]-N,N-dimethylanilinium chloride

In the title compound, C₉H₁₃N₂O⁺·Cl⁻, the cation, apart from the methyl groups, is almost planar, with a maximum deviation of 0.040 (1) Å; the methyl C atoms deviate by 0.389 (2) and −1.247 (1) Å, from the mean plane. In the crystal, cations and anions associate through C—H⋯Cl hydrogen bonds, forming a helical arrangement. In addition, inter­molecular O—H⋯Cl, N—H⋯Cl and C—H⋯N inter­actions are observed.

Biodiesel Production from Oleaginous Fungi

Biodiesel involves the mixture of fatty acyl methyl/ethyl esters, produced from transesterification neutral lipids and if the origin of the source is from oleaginous micro organisms, then it is termed as micro diesel. In the present work, aiming to exploit fungi for biodiesel production, 12 fungal isolates were screened for lipid content by Sudan Black B staining method. Among 12 isolates, lipid rich five species viz, Mortierella alpina , M.ramanianna, M.vinancea, M.hyalina and M.verticella have been taken for fatty acids analysis by spectrophotometry, which revealed that the amount of free fatty acids were ranged from highest in M.alpina 35 ?moles of Oleic acid , 25 ?moles of Palmitic acid and 14 ?moles of Myristic acids to lower as much as 21 ?moles of Oleic acid , 18 ?moles of Palmitic acid and 16 ?moles of Myristic acids respectively in M.ramanianna. DOI: http://dx.doi.org/10.3126/ijls.v6i1.5721

Bilateral tibial stress fractures: a case report

A stress fracture can be defined as a fracture of a bone caused by repeated (rather than sudden) mechanical stress. They have been reported in almost all bones of the body, with the lower extremity weight bearing bones, especially the tibia, tarsals and metatarsals, being affected most often. These injuries have a broad spectrum of severity and prognosis. Although the pathology of this injury is understood, the aetiology is less agreed upon. This can make it difficult for clinicians to diagnose and treat this common injury. Stress fractures of the proximal tibiae are common in elderly patients with osteoarthritis, and they are also reported in children. Here, we report an unusual case of an otherwise fit, young, adult male who presented with bilateral insufficiency stress fractures occurring simultaneously in both proximal tibiae. Stress fractures should be a differential diagnosis in any young, fit adult who presents with spontaneous knee pain.

1',1''-Dimethyl-4'-(naphthalen-1-yl)-1,2,3,4-tetra-hydro-naphthalene-2-spiro-3'-pyrrolidine-2'-spiro-3''-indoline-1,2''-dione

In the title compound, C₃₂H₂₈N₂O₂, the pyrrolidine ring adopts an envelope conformation, whereas the cyclo­hexa­none ring in the tetra­hydro­naphthalene fused-ring system adopts a half-chair conformation. The oxindole ring system is oriented at an angle of 48.2 (1)° with respect to the naphthyl ring system. An intra­molecular C—H⋯O close contact is observed. In the crystal, mol­ecules associate via two C—H⋯O hydrogen bonds, forming R₂²(14) and R₂²(10) dimers.

1'-Methyl-4'-(1-naphth-yl)-1'',2'',3'',4''-tetra-hydro-indane-2-spiro-2'-pyrrolidine-3'-spiro-2''-naphthalene-1,3,1''-trione

In the title compound, C₃₂H₂₅NO₃, the pyrrolidine ring adopts an envelope conformation, whereas the cyclo­hexa­none ring in the tetra­hydro­naphthalene fused-ring system adopts a half-chair conformation. The indanedione unit is oriented at an angle of 58.9 (1)° with respect to the naphthyl ring system. Three intra­molecular C—H⋯O close contacts and an intra­molecular C—H⋯π inter­action are observed. In the crystal, mol­ecules associate via C—H⋯O hydrogen bonds, forming a helical chain with a C(10) motif along the b axis.

Sorafenib and its tosylate salt: a multikinase inhibitor for treating cancer

Sorafenib, a drug that targets malignant cancer cells and cuts off the blood supply feeding the tumour, has been crystallized as the free base, 4-(4-{3-[4-chloro-3-(trifluoromethyl)phenyl]ureido}phenoxy)-N-methylpyridine-2-carboxamide, C(21)H(16)ClF(3)N(4)O(3), (I), and as a tosylate salt, 4-(4-{3-[4-chloro-3-(trifluoromethyl)phenyl]ureido}phenoxy)-2-(N-methylcarbamoyl)pyridinium 4-methylbenzenesulfonate, C(21)H(17)ClF(3)N(4)O(3)(+)·C(7)H(7)O(3)S(-), (II). In both structures, the sorafenib molecule is in an extended conformation. The pyridine-2-carboxamide group exhibits a syn conformation of the N atoms in (I), whereas an almost anti orientation is present in (II). In both crystal structures, the two terminal groups, viz. pyridine-2-carboxamide and the trifluorophenyl ring, are oriented differently to the conformations found in enzyme-bound sorafenib. The sorafenib molecules in (I) are linked into zigzag chains by N-H···O hydrogen bonds, whereas in (II) the presence of the additional tosylate anion results in the formation of chains of fused hydrogen-bonded rings. This study reveals the variations in the solid-state conformation of the sorafenib molecule in different crystalline environments.

Methyl 3-[(1H-benzimidazol-1-yl)methyl]-1-methyl-4-(4-methylphenyl)-2′-oxopyrrolidine-2-spiro-3′-1-benzimidazole-3-carboxylate

In the title compound, C₂₉H₂₈N₄O₃, the pyrrolidine ring adopts a twist conformation whereas the oxindole and benzimidazole residues are approximately planar with maximum deviations of 0.159 (1) and 0.011 (1) Å, respectively. The oxindole residue is almost perpendicular to the benzimidazole residue, making a dihedral angle of 89.2 (1)°. The methyl-substituted benzene ring is oriented at angles of 47.7 (1) and 71.0 (1)°, respectively, with respect to the oxindole and benzimidazole residues. An intra­molecular C—H⋯O hydrogen bond is observed. In the crystal, mol­ecules associate via N—H⋯N hydrogen bonds, forming R₂²(9) dimers.

Methyl 4-(4-chlorophenyl)-3,3a,4,4a,5,12c-hexahydro-2-thianaphtho[1′,2′:3,2]furo[5,4-b]pyrrolizine-4a-carboxylate

In the title compound, C₂₅H₂₂ClNO₃S, both the pyrrolidinyl and thia­zolyl rings adopt envelope conformations whereas the dihydro­pyran ring adopts a half-chair conformation. The chloro­phenyl and naphthalenyl ring systems are oriented at a dihedral angle of 59.7 (1)°. The crystal packing is stabilized by an intra­molecular C—H⋯N hydrogen bond and weak inter­molecular C—H⋯π inter­actions.

Methyl 4-phenyl-1,2,3,3a,4,4a,5,12c-octa-hydronaphtho[1',2':3,2]furo[5,4-b]pyrrolizine-4a-carboxyl-ate

In the title compound, C₂₆H₂₅NO₃, both pyrrolidine rings adopt envelope conformations, whereas the dihydro­pyran ring adopts a half-chair conformation. The phenyl ring is oriented at an angle of 27.9 (1)° with respect to the naphthalene ring system. An intra­molecular C—H⋯O hydrogen bond is observed. The crystal packing is stabilized by weak inter­molecular C—H⋯π inter­actions.

Multicomponent crystals of erlotinib

Erlotinib [systematic name: N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine], a small-molecule epidermal growth factor receptor inhibitor, useful for the treatment of non-small-cell lung cancer, has been crystallized as erlotinib monohydrate, C(22)H(23)N(3)O(4).H(2)O, (I), the erlotinib hemioxalate salt [systematic name: 4-amino-N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-1-ium hemioxalate], C(22)H(24)N(3)O(4)(+).0.5C(2)O(4)(2-), (II), and the cocrystal erlotinib fumaric acid hemisolvate dihydrate, C(22)H(23)N(3)O(4).0.5C(4)H(4)O(4).2H(2)O, (III). In (II) and (III), the oxalate anion and the fumaric acid molecule are located across inversion centres. The water molecules in (I) and (III) play an active role in hydrogen-bonding interactions which lead to the formation of tetrameric and hexameric hydrogen-bonded networks, while in (II) the cations and anions form a tetrameric hydrogen-bonded network in the crystal packing. The title multicomponent crystals of erlotinib have been elucidated to study the assembly of molecules through intermolecular interactions, such as hydrogen bonds and aromatic pi-pi stacking.

Crystal and molecular structures of 4-aryl-1,4-dihydropyrimidines: Novel calcium channel antagonists

The solid-state structures of three calcium channel antagonists viz. 1,4-dihydro-6-methyl-5-N-methyl-carbamoyl-4-(3′,4′-dichlorophenyl)-2(3 H)-pyrimidinethione, C13H13N3OSCl2 (1); 1,4-dihydro-6-methyl-5-N-methyl-carbamoyl-4-(4′-methoxyphenyl)-2(3 H)-pyrimidinethione, C14H17N3O2S (2) and 1,4-dihydro-6-methyl-5-N-methyl-carbamoyl-4-(2′,4′-dichlorophenyl)-2(3 H)-pyrimidineone monohydrate, C13H13N3O2Cl2·H2O (3), are reported here. The structures show that these compounds can adopt the important structural features of 1,4-dihydropyridine calcium channel blockers. In (2), the compound crystallized with three molecules in the asymmetric unit. The dihydropyrimidine ring adopts a half-chair in (1) and boat conformation in (2) and (3). The 4-aryl substituents occupies a pseudo-axial position approximately orthogonal to the plane of the dihydropyrimidine ring [95.1(2)° (1); 97.5(3)°, 79.8(2)° & 88.2(2)° (2) and 78.8(3)° (3)]. The C3 substituent, carbamoyl group, is in an extended conformation and oriented anticlinical in (1) and (3), but in (2) two molecules are anticlinal and the other one is synperiplanar, respectively. Intra- and inter- molecular interactions may be influencing the orientation of the C3 carbamoyl group. The 2-chlorophenyl substituent in (3) is in the axial synperiplanar orientation.

A neo-clerodane diterpene from Teucrium tomentosum. Corrigendum

Corrigendum to Acta Cryst. (2004), E60, o117–o119.

The chemical name of the title compound in the paper by Devi, Malathi, Rajan, Aravind, Krishnakumari & Ravikumar [Acta Cryst. (2004), E60, o117–o119] is corrected and the structural diagram is updated.

Methyl 2-(2,2,4-trimethyl-6-tosylperhydro-1,3-dioxino[5,4-c]pyridin-5-yl)acetate

The title compound, C₂₀H₂₉NO₆S, crystallizes with two mol­ecules in the asymmetric unit, with similar conformations. The dioxane and pyridine rings adopt twist conformations in both mol­ecules. The packing is stabilized by inter­molecular C—H⋯O hydrogen bonds.

Darifenacin hydro-bromide

In the title compound {systematic name: (S)-3-[(aminocar­bonyl)diphenylmethyl]-1-[2-(2,3-di­hy­dro­benzofuran-5-yl)ethyl]pyrrolidinium bromide}, C₂₈H₃₁N₂O₂⁺·Br⁻, the pyrrolidine rings adopts an envelope conformation. The two phenyl rings make a dihedral angle of 72.5 (1)°. The four coplanar atoms of the pyrrolidine ring makes dihedral angles of 33.1 (2) and 82.8 (2)° with the two phenyl rings. The mol­ecular conformation is influenced by a C—H⋯O inter­action. In the crystal packing, there are two N—H⋯Br hydrogen bonds running in opposite directions. They appear to form C(10) and C(9) chain motifs in the unit cell. In addition, the mol­ecular packing is further stabilized by C—H⋯Br and C—H⋯O hydrogen bonds. The C atom bonded to the benzofuran ring system is disordered in a 0.66:0.34 ratio.