Continuous decision to wait for a future reward is guided by fronto-hippocampal anticipatory dynamics.

Deciding whether to wait for a future reward is crucial for surviving in an uncertain world. While seeking rewards, agents anticipate a reward in the present environment and constantly face a trade-off between staying in their environment or leaving it. It remains unclear, however, how humans make continuous decisions in such situations. Here, we show that anticipatory activity in the anterior prefrontal cortex, ventrolateral prefrontal cortex, and hippocampus underpins continuous stay-leave decision-making. Participants awaited real liquid rewards available after tens of seconds, and their continuous decision was tracked by dynamic brain activity associated with the anticipation of a reward. Participants stopped waiting more frequently and sooner after they experienced longer delays and received smaller rewards. When the dynamic anticipatory brain activity was enhanced in the anterior prefrontal cortex, participants remained in their current environment, but when this activity diminished, they left the environment. Moreover, while experiencing a delayed reward in a novel environment, the ventrolateral prefrontal cortex and hippocampus showed anticipatory activity. Finally, the activity in the anterior prefrontal cortex and ventrolateral prefrontal cortex was enhanced in participants adopting a leave strategy, whereas those remaining stationary showed enhanced hippocampal activity. Our results suggest that fronto-hippocampal anticipatory dynamics underlie continuous decision-making while anticipating a future reward.

Healthy dietary choices involve prefrontal mechanisms associated with long-term reward maximization but not working memory.

Taste and health are critical factors to be considered when choosing foods. Prioritizing healthiness over tastiness requires self-control. It has also been suggested that self-control is guided by cognitive control. We then hypothesized that neural mechanisms underlying healthy food choice are associated with both self-control and cognitive control. Human participants performed a food choice task and a working memory task during functional MRI scanning. Their degree of self-control was assessed behaviorally by the value discount of delayed monetary rewards in intertemporal choice. Prioritizing healthiness in food choice was associated with greater activity in the superior, dorsolateral, and medial prefrontal cortices. Importantly, the prefrontal activity was greater in individuals with smaller delay discounting (i.e. high self-control) who preferred a delayed larger reward to an immediate smaller reward in intertemporal choice. On the other hand, working memory activity did not show a correlation with delay discounting or food choice activity, which was further supported by supplementary results that analyzed data from the Human Connectome Project. Our results suggest that the prefrontal cortex plays a critical role in healthy food choice, which requires self-control, but not working memory, for maximization of reward attainments in a remote future.

Efficient Separation of Methanol Single-Micron Droplets by Tailing Phenomenon Using a PDMS Microfluidic Device.

Microdroplet-based fluidic systems have the advantages of small size, short diffusion time, and no cross-contamination; consequently, droplets often provide a fast and precise reaction environment as well as an analytical environment for individual molecules. In order to handle diverse reactions, we developed a method to create organic single-micron droplets (S-MDs) smaller than 5 µm in diameter dispersed in silicone oil without surfactant. The S-MD generation microflow device consists of a mother droplet (MoD) generator and a tapered separation channel featuring multiple side channels. The tapered channel enhanced the shear forces to form tails from the MoDs, causing them to break up. Surface treatment with the fluoropolymer CYTOP protected PDMS fluid devices from organic fluids. The tailing separation of methanol droplets was accomplished without the use of surfactants. The generation of tiny organic droplets may offer new insights into chemical separation and help study the scaling effects of various chemical reactions.

Towards Industrially Important Applications of Enhanced Organic Reactions by Microfluidic Systems.

This review presents a comprehensive evaluation for the manufacture of organic molecules via efficient microfluidic synthesis. Microfluidic systems provide considerably higher control over the growth, nucleation, and reaction conditions compared with traditional large-scale synthetic methods. Microfluidic synthesis has become a crucial technique for the quick, affordable, and efficient manufacture of organic and organometallic compounds with complicated characteristics and functions. Therefore, a unique, straightforward flow synthetic methodology can be developed to conduct organic syntheses and improve their efficiency.

Deformability-Based Microfluidic Microdroplet Screening to Obtain Agarolytic Bacterial Cells.

Environmental microorganisms possess enzymes that can digest macromolecules such as agarose into smaller molecules that can be utilized for growth. These enzymes could be valuable for the effective utilization of global resources. However, since most of the microorganisms on Earth remain uncultured, there is significant untapped enzymatic potential in nature. Therefore, it is necessary to develop innovative tools and strategies for exploring these enzymatic resources. To address this, we developed a method for screening microbial cells that secrete hydrogel-degrading enzymes using deformability-based microfluidic microdroplet sorting. In this method, microbial cells are encapsulated as single cells in water-in-oil (W/O) microdroplets with a hydrogel whose shape becomes deformable as the hydrogel is progressively degraded into smaller molecules. Screening is achieved using a microfluidic device that passively sorts the deformed W/O microdroplets. Using this method, we successfully sorted agarose-containing microdroplets, encapsulating single bacterial cells that hydrolyzed agarose. This method can be used to screen various hydrogel-degrading microbial cells.

Clinical Utility and Patient Distribution of Brief Resolved Unexplained Event Classification for Apparent Life-Threatening Events.

OBJECTIVES: In 2016, brief resolved unexplained events (BRUEs) were proposed as alternative concepts to apparent life-threatening event (ALTE). The clinical utility of managing ALTE cases according to the BRUE classification is controversial. To verify the clinical utility of the BRUE criteria, we evaluated the proportion of ALTE patients who met and those who did not meet the BRUE criteria and assessed the diagnoses and outcomes of each group. METHODS: We retrospectively investigated patients with ALTE younger than 12 months who visited the emergency department of the National Center for Child Health and Development from April 2008 to March 2020. The patients were classified into the higher-risk and lower-risk BRUE groups; however, those who did not meet the BRUE criteria were classified into the ALTE-not-BRUE group. We evaluated the diagnoses and outcomes of each group. Adverse outcomes included death, recurrence, aspiration, choking, trauma, infection, convulsions, heart disease, metabolic disease, allergies, and others. RESULTS: Over the period of 12 years, a total of 192 patients were included, among which 140 patients (71%) were classified into the ALTE-not-BRUE group, 43 (22%) into the higher-risk BRUE group, and 9 (5%) into the lower-risk BRUE group. Adverse outcomes occurred in 27 patients in the ALTE-not-BRUE group and 10 patients in the higher-risk BRUE group. No adverse outcome occurred in the lower-risk BRUE group. CONCLUSIONS: Many of the patients with ALTE were classified into the ALTE-not-BRUE group, suggesting that replacing ALTE with BRUE is difficult. Although patients classified as lower-risk BRUE showed no adverse outcomes, there were only a few of them. In the pediatric emergency medicine setting, the BRUE risk classification may be beneficial for certain patients.

Synthesis of Cage-Shaped Borates Bearing Pyrenylmethyl Groups: Efficient Lewis Acid Catalyst for Photoactivated Glycosylations Driven by Intramolecular Excimer Formation.

We describe the synthesis and characterization of a photoactivated boron-based Lewis acid catalyst based on a cage-shaped triphenolic ligand with three pyrenylmethyl moieties. The obtained cage-shaped borate functioned as a photoactivated Lewis acid catalyst thanks to the flexible three pyrenylmethyl moieties. The deformation of the cage-shaped scaffold driven by intramolecular excimer formations of the pyrenes is a critical factor in realizing the photoactivation. Mannich-type reactions and glycosylations significantly were accelerated under 370 nm light irradiations. It is noteworthy that various glycosyl fluorides, which are not easily activated in photocatalytic systems due to their high C-F bond stability, are activated by the photoimproved catalytic activity of the catalyst.

Healing effects of monomer and dimer resveratrol in a mouse periodontitis model.

BACKGROUND: The antioxidant and anti-inflammatory effects of resveratrol have been reported previously. Particularly, monomeric trans-resveratrol has been demonstrated to produce positive effects in various pathological processes. We reported previously that resveratrol dimer-rich melinjo extract, among others, caused bone healing, decreased local oxidative damage, and activated antioxidants nuclear factor erythroid 2-related factor 2 (Nrf2) pathways in a mouse model of experimentally induced periodontitis (EP). This study aimed to compare the bone-healing effects of the resveratrol monomer to the resveratrol dimer (gnetin C found in melinjo seed extract) in a model of EP and investigate the involvement of Nrf2 for effects of either form of resveratrol. METHODS: EP was induced experimentally in mice by placement of a 9 - 0 silk ligature around the left second molar. Mice received 10 mg/kg of either resveratrol monomer or dimer intraperitoneally on day 15 after induction of EP. The bone level around the ligated teeth was measured over time, and levels of proinflammatory cytokines and oxidative stress were measured in the periodontal tissues around the ligated teeth. RESULTS: Resveratrol dimer induced greater periodontal bone healing as compared to that related to use of the resveratrol monomer. It appears that healing of periodontal bone in either group was likely related to master regulation of antioxidant nuclear factor erythroid 2-related factor 2 (Nrf2) significantly. Downregulation of IL-1ß, a proinflammatory cytokine was also demonstrated in the resveratrol dimer group. CONCLUSION: Our results showed that administration of resveratrol in either dimer form or the monomeric form reduced periodontal bone loss with greater inhibition of bone loss being demonstrated in the dimer group as compared to the monomer group and that these effects were related in all likelihood to decreased oxidative stress and hence reduction in local inflammation.

Self-Controlled Choice Arises from Dynamic Prefrontal Signals That Enable Future Anticipation.

Self-control allows humans the patience necessary to maximize reward attainment in the future. Yet it remains elusive when and how the preference to self-controlled choice is formed. We measured brain activity while female and male humans performed an intertemporal choice task in which they first received delayed real liquid rewards (forced-choice trial), and then made a choice between the reward options based on the experiences (free-choice trial). We found that, while subjects were awaiting an upcoming reward in the forced-choice trial, the anterior prefrontal cortex (aPFC) tracked a dynamic signal reflecting the pleasure of anticipating the future reward. Importantly, this prefrontal signal was specifically observed in self-controlled individuals, and moreover, interregional negative coupling between the prefrontal region and the ventral striatum (VS) became stronger in those individuals. During consumption of the liquid rewards, reduced ventral striatal activity predicted self-controlled choices in the subsequent free-choice trials. These results suggest that a well-coordinated prefrontal-striatal mechanism during the reward experience shapes preferences regarding the future self-controlled choice.SIGNIFICANCE STATEMENT Anticipating future desirable events is a critical mental function that guides self-controlled behavior in humans. When and how are the self-controlled choices formed in the brain? We monitored brain activity while humans awaited a real liquid reward that became available in tens of seconds. We found that the frontal polar cortex tracked temporally evolving signals reflecting the pleasure of anticipating the future reward, which was enhanced in self-controlled individuals. Our results highlight the contribution of the fronto-polar cortex to the formation of self-controlled preferences, and further suggest that future prospect in the prefrontal cortex (PFC) plays an important role in shaping future choice behavior.

Oral infectious bacteria in dental plaque and saliva as risk factors in patients with esophageal cancer.

BACKGROUND: High levels of periodontopathic bacteria as well as Streptococcus anginosus were detected in cancer tissue from patients with esophageal cancer. An association between oral infectious bacteria and esophageal cancer has been reported. METHODS: Characteristics of the oral microbiota and periodontal conditions were studied as clinicopathologic factors in patients with esophageal cancer. The study included 61 patients with esophageal cancer and 62 matched individuals without any cancers. Samples of subgingival dental plaque and unstimulated saliva were collected to evaluate the prevalence and abundance of the following oral bacteria using a real-time polymerase chain reaction assay: Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Treponema denticola, and S. anginosus. RESULTS: In the cancer group, the prevalence of all bacteria, with the exception of F. nucleatum, in dental plaque; the prevalence of A. actinomycetemcomitans in saliva; the abundance of all bacteria, with the exception of F. nucleatum and P. intermedia, in dental plaque; and the abundance of A. actinomycetemcomitans and S. anginosus in saliva were significantly higher. Furthermore, a logistic regression analysis suggested that the prevalence of T. forsythia and S. anginosus in dental plaque and of A. actinomycetemcomitans in saliva, as well as a drinking habit, were associated with a high risk of esophageal cancer, with a high odds ratio. CONCLUSIONS: The current findings have potential implications for the early diagnosis of esophageal cancer.

Vegetable-Derived Carbapenemase-Producing High-Risk Klebsiella pneumoniae ST15 and Acinetobacter baumannii ST2 Clones in Japan: Coexistence of blaNDM-1, blaOXA-66, blaOXA-72, and an AbaR4-Like Resistance Island in the Same Sample.

This study was conducted to characterize carbapenemase-producing Klebsiella pneumoniae and Acinetobacter baumannii isolated from fresh vegetables in Japan. Two K. pneumoniae isolates (AO15 and AO22) and one A. baumannii isolate (AO22) were collected from vegetables in the city of Higashihiroshima, Japan, and subjected to antimicrobial susceptibility testing, conjugation experiments, and complete genome sequencing using Illumina MiniSeq and Oxford Nanopore MinION sequencing platforms. The two K. pneumoniae isolates were clonal, belonging to sequence type 15 (ST15), and were determined to carry 19 different antimicrobial resistance genes, including blaNDM-1 Both the isolates carried blaNDM-1 on a self-transmissible IncFII(K):IncR plasmid of 122,804 bp with other genes conferring resistance to aminoglycosides [aac(6')-Ib, aadA1, and aph(3')-VI], ß-lactams (blaCTX-M-15, blaOXA-9, and blaTEM-1A), fluoroquinolones [aac(6')-Ib-cr], and quinolones (qnrS1). A. baumannii AO22 carried blaOXA-66 on the chromosome, while blaOXA-72 was found as two copies on a GR2-type plasmid of 10,880 bp. Interestingly, A. baumannii AO22 harbored an AbaR4-like genomic resistance island (GI) of 41,665 bp carrying genes conferring resistance to tetracycline [tet(B)], sulfonamides (sul2), and streptomycin (strAB). Here, we identified Japanese carbapenemase-producing Gram-negative bacteria isolated from vegetables, posing a food safety issue and a public health concern. Additionally, we reported a GR2-type plasmid carrying two copies of blaOXA-72 and an AbaR4-like resistance island from a foodborne A. baumannii isolate.IMPORTANCE Carbapenemase-producing Gram-negative bacteria (CPGNB) cause severe health care-associated infections and constitute a major public health threat. Here, we investigated the genetic features of CPGNB isolated from fresh vegetable samples in Japan and found CPGNB, including Klebsiella pneumoniae and Acinetobacter baumannii, with dissimilar carbapenemases. The NDM carbapenemase, rarely described in Japan, was detected in two K. pneumoniae isolates. The A. baumannii isolate identified in this study carried blaOXA-66 on the chromosome, while blaOXA-72 was found as two copies on a GR2-type plasmid. This study indicates that even one fresh ready-to-eat vegetable sample might serve as a significant source of genes (blaNDM-1, blaOXA-72, blaCTX-M-14b, and blaCTX-M-15) encoding resistance to frontline and clinically important antibiotics (carbapenems and cephalosporins). Furthermore, the detection of these organisms in fresh vegetables in Japan is alarming and poses a food safety issue and a public health concern.

Efficient Generation of Microdroplets Using Tail Breakup Induced with Multi-Branch Channels.

In recent years, research on the application of microdroplets in the fields of biotechnology and chemistry has made remarkable progress, but the technology for the stable generation of single-micrometer-scale microdroplets has not yet been established. In this paper, we developed an efficient and stable single-micrometer-scale droplet generation device based on the fragmentation of droplet tails, called "tail thread mode", that appears under moderate flow conditions. This method can efficiently encapsulate microbeads that mimic cells and chemical products in passively generated single-micrometer-scale microdroplets. The device has a simple 2D structure; a T-junction is used for droplet generation; and in the downstream, multi-branch channels are designed for droplet deformation into the tail. Several 1-2 µm droplets were successfully produced by the tail's fragmentation; this continuous splitting was induced by the branch channels. We examined a wide range of experimental conditions and found the optimal flow rate condition can be reduced to one-tenth compared to the conventional tip-streaming method. A mold was fabricated by simple soft lithography, and a polydimethylsiloxane (PDMS) device was fabricated using the mold. Based on the 15 patterns of experimental conditions and the results, the key factors for the generation of microdroplets in this device were examined. In the most efficient condition, 61.1% of the total droplets generated were smaller than 2 µm.

A comparative questionnaire study of patient complaint levels between magnetostrictive ultrasonic scaler (Cavitron® ) and piezoelectric ultrasonic scalers.

OBJECTIVES: Ultrasonic scalers often cause an uncomfortable feeling to patients during the procedure. This study was conducted to compare patient complaint levels between magnetostrictive (M-USSC) and piezoelectric ultrasonic scalers (P-USSC) during supragingival scaling. METHODS: This study enrolled 82 subjects who received supportive periodontal therapy for at least 2 years. At each recall visit, probing pocket depth (PPD), bleeding on probing (BOP) and O'Leary plaque control record (O'PCR) were recorded. Then, supragingival scaling was performed using P-USSC (Varios or Petit Piezo) at the first visit and M-USSC (Cavitron) at the second visit. After each treatment, a questionnaire survey was performed using the Wong-Baker Faces Pain Scale for six items, which included the typical complaints occurring during ultrasonic scaling. RESULTS: The scores for all the six items related to patient complaints were greater for P-USSC than for M-USSC (p < 0.001). Patient complaints such as discomfort, pain, sound, vibration, hyperesthesia and length of treatment time were ameliorated in 74%, 65%, 80%, 67%, 57% and 53% of subjects using M-USSC, respectively. On the other hand, only <5% of subjects showed deterioration in terms of each complaint. CONCLUSION: This study suggested that M-USSC causes fewer patient complaints during supragingival scaling than P-USSC. M-USSC may improve patient motivation and compliance and may contribute towards achieving successful treatment outcomes. However, this result could differ depending on the shape of the tip and the insert and treatment site. Further research will be required under various conditions.

Selective Activation of Aromatic Aldehydes Promoted by Dispersion Interactions: Steric and Electronic Factors of a π-Pocket within Cage-Shaped Borates for Molecular Recognition.

Selective bond formations are one of the most important reactions in organic synthesis. In the Lewis acid mediated electrophile reactions of carbonyls, the selective formation of a carbonyl-acid complex plays a critical role in determining selectivity, which is based on the difference in the coordinative interaction between the carbonyl and Lewis acid center. Although this strategy has attained progress in selective bond formations, the discrimination between similarly sized aromatic and aliphatic carbonyls that have no functional anchors to strongly interact with the metal center still remains a challenging issue. Herein, this work focuses on molecular recognition driven by dispersion interactions within some aromatic moieties. A Lewis acid catalyst with a π-space cavity, which is referred to as a π-pocket, as the recognition site for aromatic carbonyls is designed. Cage-shaped borates 1B with various π-pockets demonstrated significant chemoselectivity for aromatic aldehydes 3 b-f over that of aliphatic 3 a in competitive hetero-Diels-Alder reactions. The effectiveness of our catalysts was also evidenced by intramolecular recognition of the aromatic carbonyl within a dicarbonyl substrate. Mechanistic and theoretical studies demonstrated that the selective activation of aromatic substrates was driven by the preorganization step with a larger dispersion interaction, rather than the rate-determining step of the C-C bond formation, and this was likely to contribute to the preferred activation of aromatic substrates over that of aliphatic ones.

Development of Microdroplet Generation Method for Organic Solvents Used in Chemical Synthesis.

Recently, chemical operations with microfluidic devices, especially droplet-based operations, have attracted considerable attention because they can provide an isolated small-volume reaction field. However, analysis of these operations has been limited mostly to aqueous-phase reactions in water droplets due to device material restrictions. In this study, we have successfully demonstrated droplet formation of five common organic solvents frequently used in chemical synthesis by using a simple silicon/glass-based microfluidic device. When an immiscible liquid with surfactant was used as the continuous phase, the organic solvent formed droplets similar to water-in-oil droplets in the device. In contrast to conventional microfluidic devices composed of resins, which are susceptible to swelling in organic solvents, the developed microfluidic device did not undergo swelling owing to the high chemical resistance of the constituent materials. Therefore, the device has potential applications for various chemical reactions involving organic solvents. Furthermore, this droplet generation device enabled control of droplet size by adjusting the liquid flow rate. The droplet generation method proposed in this work will contribute to the study of organic reactions in microdroplets and will be useful for evaluating scaling effects in various chemical reactions.

Synthesis of Cage-Shaped Aluminum Aryloxides: Efficient Lewis Acid Catalyst for Stereoselective Glycosylation Driven by Flexible Shift of Four- to Five-Coordination.

Monomeric cage-shaped aluminum aryl oxides 1Al were synthesized using tripodal triphenolic ligands. The Lewis acidity and catalytic activity of the obtained 1Al·py were investigated. The Lewis acidity of 1Al·py originates from the flexible change in the coordination number of the aluminum center, allowing the catalytic O-glycosylation to occur with a high efficiency and an unusual stereoselectivity.

Silicon nitride sugar chips for detection of Ricinus communis proteins and Escherichia coli O157 Shiga toxins.

Lactosides having either an amino-triethylene glycol or an azido-triethylene glycol were designed and synthesized, and the two derivatives were immobilized onto silicon nitride (SiN) surfaces. When a click reaction was applied for the immobilization of the azido-sugar, a Ricinus communis lectin (RCA120) was detected with a higher response by reflectometric interference spectroscopy (RIfS). When an N-hydroxysuccinimide (NHS) method was applied for the sugar immobilization, the response was less than that of the click one. The response of bovine serum albumin (BSA) as the negative control was negligible, but the lactose-SiN chip prepared by the click method suppressed nonspecific binding more effectively than did the chip from the NHS method. Next, we examined an antibody-immobilized SiN chip prepared by the click reaction. The detection response was, however, lower than that of the lactose-SiN chip, meaning that the sugar-chip by the click reaction was superior to the antibody-chip. Finally, to detect Shiga toxins from Escherichia coli O157:H7, globotrisaccharide (Gb3) with an azido-triethylene glycol was synthesized and immobilized onto the SiN chip by the click reaction. The Gb3-SiN chips enabled us to detect the toxins at concentrations less than 100 ng/mL. RCA120, horse gram, gorse lectins and BSA showed no response to the Gb3-SiN chip, showing a high specificity for the toxin.

Microfluidic Stamping on Sheath Flow.

A microfluidic stamping method to form functional shapes on a cross section in fiber-shaped flow is proposed. Microfluidic stamping and overstamping allow various cross sectional shapes on the 3D flow. The shapes can be controlled by a change in combination of structures and fluidic conditions which correspond to stamp type and stamping force.

Behavioral and histological analyses of the mouse Bassoon p.P3882A mutation corresponding to the human BSN p.P3866A mutation.

Tauopathy is known to be a major pathognomonic finding in important neurodegenerative diseases such as progressive supranuclear palsy (PSP) and corticobasal degeneration. However, the mechanism by which tauopathy is triggered remains to be elucidated. We previously identified the point mutation c.11596C > G, p.Pro3866Ala in the Bassoon gene (BSN) in a Japanese family with PSP-like syndrome. We showed that mutated BSN may have been involved in its own insolubilization and tau accumulation. Furthermore, BSN mutations have also been related to various neurological diseases. In order to further investigate the pathophysiology of BSN mutation in detail, it is essential to study it in mouse models. We generated a mouse model with the mouse Bassoon p.P3882A mutation, which corresponds to the human BSN p.P3866A mutation, knock-in (KI) and we performed systematic behavioral and histological analyses. Behavioral analyses revealed impaired working memory in a Y-maze test at 3 months of age and decreased locomotor activity in the home cage at 3 and 12 months of age in KI mice compared to those in wild-type mice. Although no obvious structural abnormalities were observed at 3 months of age, immunohistochemical studies showed elevation of Bsn immunoreactivity in the hippocampus and neuronal loss without tau accumulation in the substantia nigra at 12 months of age in KI mice. Although our mice model did not show progressive cognitive dysfunction and locomotor disorder like PSP-like syndrome, dopaminergic neuronal loss was observed in the substantia nigra in 12-month-old KI mice. It is possible that BSN mutation may result in dopaminergic neuronal loss without locomotor symptoms due to the early disease stage. Thus, further clinical course can induce cognitive dysfunction and locomotor symptoms.

Concise synthesis of well-defined linear and branched oligothiophenes with nickel-catalyzed regiocontrolled cross-coupling of 3-substituted thiophenes by catalytically generated magnesium amide.

The synthesis of linear and branched oligothiophenes of well-defined structures is performed with regioselective deprotonation of 3-substituted thiophenes and nickel-catalyzed cross-coupling of the thus formed metalated species with a bromothiophene. The reaction of 3-hexylthiophene with EtMgCl and 2,2,6,6-tetramethylpiperidine (TMP-H, 10 mol%) induces the metalation selectively at the 5-position by use of the catalytically generated hindered magnesium amide (TMPMgCl) and the subsequent reaction of a 2-halo-3-hexylthiophene (bromide or chloride) in the presence of a nickel catalyst affords a head-to-tail (HT)-type dimer. By repeating the same sequence, the linear oligothiophene up to a 4-mer is synthesized in good yield. The reaction of 3-hexylthiophene with 2,3-dibromothiophene also takes place to afford a branched oligothiophene 3-mer in quantitative yield. The obtained 3-mer is also metalated at the sterically less-hindered position in a regioselective manner furnishing a 7-mer in >99% yield after a further coupling reaction with 2,3-dibromothiophene. These dendrimers react with several multifunctionalized organic electrophiles, leading to a variety of branched oligothiophenes.