Restriction of memory B cell differentiation at the germinal center B cell positive selection stage

Memory B cells (MBCs) are key for protection from reinfection. However, it is mechanistically unclear how germinal center (GC) B cells differentiate into MBCs. MYC is transiently induced in cells fated for GC expansion and plasma cell (PC) formation, so-called positively selected GC B cells. We found that these cells coexpressed MYC and MIZ1 (MYC-interacting zinc-finger protein 1 [ZBTB17]). MYC and MIZ1 are transcriptional activators; however, they form a transcriptional repressor complex that represses MIZ1 target genes. Mice lacking MYC-MIZ1 complexes displayed impaired cell cycle entry of positively selected GC B cells and reduced GC B cell expansion and PC formation. Notably, absence of MYC-MIZ1 complexes in positively selected GC B cells led to a gene expression profile alike that of MBCs and increased MBC differentiation. Thus, at the GC positive selection stage, MYC-MIZ1 complexes are required for effective GC expansion and PC formation and to restrict MBC differentiation. We propose that MYC and MIZ1 form a module that regulates GC B cell fate

Liveweight gain and feed intake of weaned Bali cattle fed a range of diets in Central Sulawesi, Indonesia

Three experiments were conducted to determine liveweight (W) gain and feed and water intake of weaned Bali cattle offered a range of feed types. In each experiment, 18 weaned entire male Bali cattle were allocated to three treatment groups in a completely randomised block design, with six replicates (animals) per treatment. The dietary treatments were: Experiment 1, native grass fed ad libitum, native grass supplemented with rice bran at 10 g dry matter (DM)/kg W.day and native grass supplemented with a mixture of rice bran and copra meal in equal proportions fed at 10 g DM/kg W.day; Experiment 2, elephant grass hay fed ad libitum, elephant grass supplemented with gliricidia at 10 g DM/kg W.day, and gliricidia fed ad libitum; and Experiment 3, corn stover fed ad libitum, corn stover supplemented with gliricidia at 10 g DM/kg W.day, and corn stover supplemented with rice bran/copra meal in equal amounts (w/w) at 10 g DM/kg W.day. Each experiment was 10 weeks in duration, consisting of a 2-week preliminary period for adaptation to diets and an 8-week experimental period for the measurement of W change, feed and water intake and digestibility of the diet. Growth rates of 612-month-old, entire male Bali cattle fed a range of local diets ranged from 0.10 and 0.40 kg/day. Lowest growth rates occurred when the cattle were given the basal diets of native grass (0.104 kg/day), elephant grass (0.174 kg/day) and corn stover (0.232 kg/day). With the addition of supplements such as rice bran, rice bran/copra meal or gliricidia to these basal diets liveweight gains increased to between 0.225 and 0.402 kg/day. Forage DM intake was reduced with these supplements by on average 22.6% while total DM intake was increased by an average of 10.5%. The growth rate on gliricidia alone was 0.269 kg/day and feed DM intake was 28.0 g/kg W.day. Water intake was not affected by supplement type or intake. In conclusion, inclusion of small quantities of locally available, high quality feed supplements provide small-holder farmers with the potential to increase growth rates of Bali calves from 0.1 to 0.2 kg/day, under prevailing feeding scenarios, to over 0.4 kg/day

Présentation atypique d'une duplication intestinale chez un enfant de trois mois

Intestinal duplication is an uncommon congenital anomaly that often is diagnosed during childhood. Ultrasound diagnosis is based on the presence of a characteristic double-walled cystic mass. We report a case of duplication in a three month old child presenting with small bowel obstruction. This case is unusual due to the presence of calcifications that are uncommon in intestinal duplication.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Tolosa-hunt syndrome in children

We report a case of Tolosa-Hunt syndrome in a 4-year-old girl. Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) revealed a left cavernous sinus involvement with internal carotid artery occlusion. Clinical signs included left ophthalmoplegia, convulsions and right hemiplegia. Etiopathogenesis of this syndrome is unclear but as in our case, response to corticosteroid therapy is spectacular and avoids unnecessary invasive diagnostic procedures. We underline the importance of cross-sectional imaging in the diagnostic approach. Several other diseases including tumors, vascular lesions and infections can have a similar clinical and/or imaging presentation. However, closely monitored evolution on imaging proves to be decisive in the establishment of final diagnosis of this syndrome

Topological Dirac semi-metals as novel, optically-switchable, helicity-dependent terahertz sources

The generation and control of terahertz pulses is vital for realizing the potential of terahertz radiation in several sectors, including 6G communication, security and imaging. In this work, we present the topological Dirac semimetal cadmium arsenide as a novel helicity-dependent terahertz source. We show both broadband (single-cycle) and narrowband (multi-cycle) terahertz pulses upon near-infrared photoexcitation at oblique incidence. By varying the incident angle of the photoexcitation pulse, control of the emission frequency can also be achieved, providing a candidate for a tuneable narrowband terahertz source

Tracking electron and hole dynamics in 3D dirac semimetals

Using ultrafast optical-pump terahertz-probe spectroscopy (OPTP) and ultrafast terahertz emission spectroscopy, we showcase the electron and hole dynamics in Cd3As2 nanowires (NWs), a well-known 3D Dirac semimetal a subgroup of the newly discovered . A temperature-dependent photoconductivity measurement was carried out yielding an incredibly high electron mobility ~ 16,000 cm2/Vs at 5K. Strong THz emission due to helicity-dependent surface photocurrents was also observed for both nanowires and single crystal (SC) which is highly desirable for devices such as THz sources

Terahertz characterization of charge carrier dynamics in 3D Dirac semi-metal Cd3As2 nanowires

Optical Pump Terahertz Probe (OPTP) spectroscopy is a well-established measurement technique with which charge-carrier dynamics of semiconductor nanowires (NW) can be extracted in a noncontact manner. Here in this work, we employ OPTP spectroscopy for measuring temperature-dependent photoconductivity spectra of 3D Dirac Cd 3 As 2 semi-metal nanowires, revealing a high Extrinsic carrier concentration of ∼2.0x1017cm−3 and ultrahigh carrier mobility of up to ∼13x103cm2V−1s−1 at a temperature of 5 K

Feeding selenium-rich fermented palm kernel cake to laying hens produces selenium-rich eggs, increases egg production and quality

A study was conducted to determine the effect of selenium (sodium selenite) added to palm kernel cake (PKC) before fermentation on production, selenium content, and quality of eggs. The PKC was added with 0.1% sodium selenite and 1% baking yeast (Fermipan®). The mixture was added with ster-ile distilled water to increase the water content of the substrate. The substrates were fermented at room temperature for 5 days. The fermented products of selenium-rich fermented palm kernel cake (SRFPKC) were dried and fed to the laying hens. The experimental diets used were T-0: without SRF-PKC, T-1: 0.25% SRFPKC, T-2: 0.50% SRFPKC, T-3: 0.75% SRFPKC and T-4: 1.0 % SRFPKC. The diets were given to 180 laying hens aged 22 weeks for 14 weeks. Data on egg production, feed intake and feed conversion ratio were recorded. Feed digestibilities of dry matter and protein were measured based on the method of total fecal collection. Egg qualities and egg weight loss were done using eggs stored for 1 and 30 days. Selenium and cholesterol contents of eggs were also measured. This study used a completely randomized design and was analyzed by analysis of variance. The results showed that the addition of SRFPKC increased egg production, hen day, egg weight, egg selenium, feed digest-ibility, improve FCR (P<0.05) and inhibit the process of decreasing the quality and weight of eggs stored for 30 days (P<0.05). In conclusion, the addition of SRFPKC increased egg production, feed digestibility, and egg selenium, improve FCR and slow down the deterioration of egg quality stored for 30 days