Supplementation with long-acting progesterone in early diestrus in beef cattle: II. Relationships between follicle growth dynamics and luteolysis.

The aims were to characterize follicular dynamics in response to supplemental progesterone (P4) and to investigate the relationships between follicular growth and onset of luteolysis in P4-treated cows, submitted or not to artificial insemination (AI). Nonsuckled beef cows detected in estrus were assigned to receive AI or to remain non-AI. Three days after ovulation (ie, D3), AI cows were injected with 150 mg of long-acting P4 (AI + injectable P4 formulation [iP4]; n = 22), and the non-AI cows were assigned to receive 150 mg iP4 (n = 19) or saline (control, n = 19). Between D3 and D21, growth dynamics of the dominant follicles (DFs) was monitored by ultrasonography. Plasma P4 concentrations were measured every other day from D9 to D19. Pregnancy status (ie, P: pregnant and NP: nonpregnant) was examined by ultrasound on D28 to D32. Injectable P4 formulation supplementation decreased average maximum diameter of first-wave DF (DF1). Neither day of emergence of DF2 or DF3 nor the proportion of two- or three-wave cycles were altered by supplemental P4. Daily mean diameter of DF2 and DF3 was also similar between control and iP4 groups. Consistently, daily mean diameter of DF1 in iP4-treated cows was smaller for cows that underwent luteolysis by D15 compared to a later onset. Progesterone concentrations between D9 and D19 decreased earliest in the iP4 group, latest in the control group and was intermediate for the NP-AI + iP4 group. In addition, three-wave cycles presented a delayed decrease on plasma P4 concentrations than two-wave cycles. Further analysis revealed that on two-wave cycles, P4 concentrations on D15 were lowest in the iP4 and NP-AI + iP4 animals compared to the control and P-AI + iP4 groups. Conversely, for three-wave cycles, on D15, P-AI + iP4, NP-AI + iP4, and controls had greater P4 concentrations than the iP4 group. In summary, our data indicate that impairment of first follicular growth was associated with P4-induced shortened luteal lifespan (D14-D15) and that three-wave cycles after AI can be more supportive for pregnancy maintenance in P4-treated cows. We speculate that such conditions play a critical role in the embryonic ability to inhibit iP4-induced early luteolysis reported in part I of this series.

Teneurin-2 presence in rat and human odontoblasts.

Teneurins are transmembrane proteins consisting of four paralogues (Ten-1-4), notably expressed in the central nervous system during development. All teneurins contain a bioactive peptide in their carboxyl terminal named teneurin C-terminal associated peptide (TCAP). The present study analyzed the detailed distribution of teneurin-2-like immunoreactive (Ten-2-LI) cells in developing and mature rat molar teeth, as well as in mature human dental pulps. Ten-2 and TCAP-2 genic expressions were also evaluated in rat and human dental pulps. Finally, Ten-2-LI cells were analyzed during the repair process after dentin-pulp complex injury in rat lower molar teeth. For this, histological sections of rat molar teeth and human dental pulps were submitted to immunohistochemical techniques, while total RNA from developing rat teeth and mature human dental pulps were submitted to conventional RT-PCR. Ten-2-LI cells were evident in the initial bell stage of rat molar teeth development, especially in ectomesenchymal cells of the dental papilla. Ten-2-LI odontoblasts showed strong immunoreactivity in rat and human mature teeth. Ten-2 and TCAP-2 genic expressions were confirmed in rat and human dental pulps. Dentin-pulp complex injury resulted in a decrease of Ten-2-LI odontoblasts after traumatic injury. Interestingly, Ten-2-LI cells were also evident in the pulp cell-rich zone in all postoperative days. In conclusion, Ten-2-LI presence in rat and human odontoblasts was demonstrated for the first time and Ten-2/TCAP-2 genic expressions were confirmed in rat and human dental pulps. Furthermore, it was revealed that Ten-2-LI rat odontoblasts can be modulated during the regenerative process.

Neurochemistry study of spinal cord in non-human primate (Sapajus spp.).

The spinal cord is involved in local, ascending and descending neural pathways. Few studies analyzed the distribution of neuromediators in the laminae of non-human primates along all segments. The present study described the classic neuromediators in the spinal cord of the non-human primate Sapajus spp. through histochemical and immunohistochemical methods. Nicotinamide adenine dinucleotide hydrogen phosphate-diaphorase (NADPH-d) method showed neuronal somata in the intermediolateral column (IML), central cervical nucleus (CCN), laminae I, II, III, IV, V, VI, VII, VIII and X, besides dense presence of nerve fibers in laminae II and IX. Acetylcholinesterase (AChE) activity was evident in the neuronal somata in laminae V, VI, VII, VIII, IX, CCN, IML and in the Clarke's column (CC). Immunohistochemistry data revealed neuronal nitric oxide synthase (nNOS) immunoreactivity  in neuronal somata and in fibers of laminae I, II, III, VII, VIII, X and IML; choline acetyltransferase (ChAT) in neuronal somata and in fibers of laminae VII, VIII and IX; calcitonin gene-related peptide (CGRP) was noticed in neuronal somata of lamina IX and in nerve fibers of laminae I, II, III, IV, V, VI and VII; substance P (SP) in nerve fibers of laminae I, II, III, IV, V, VI, VII, VIII, IX, X, CCN, CC and IML; serotonin (5-HT) and vesicular glutamate transporter-1 (VGLUT1) was noticed in nerve fibers of all laminae;  somatostatin (SOM) in neuronal somata of laminae III, IV, V, VI, VII, VIII and IX and nerve fibers in laminae I, II, V, VI, VII, X and IML; calbindin (Cb) in neuronal somata of laminae I, II, VI, VII, IX and X; parvalbumin (PV) was found in neuronal somata and in nerve fibers of laminae III, IV, V, VI, VII, VIII, IX and CC; finally, gamma-amino butyric acid (GABA) was present in neuronal somata of laminae V, VI, VII, VIII, IX and X. This study revealed interesting results concerning the chemoarchitecture of the Sapajus spp. spinal cord with a distribution pattern mostly similar to other mammals. The data corroborate the result described in literature, except for some differences in CGRP, SP, Cb, PV and GABA immunoreactivities present in neuronal somata and in nerve fibers. This could suggest certain specificity for the neurochemistry distribution in this non-human primate species, besides adding relevant data to support further studies related to processes involving spinal cord components.

Phenotypic and genetic diversity among Bacillus sphaericus strains isolated in Brazil, potentially useful as biological control agents against mosquito larvae.

Thirty mosquitocidal strains of Bacillus sphaericus isolated from different sources and localities in Brazil were characterized phenotypically and genetically to determine their relationship. Among the strains tested, 93.3% were shown to be resistant to lincomycin, 96.6% to novobiocin, 60% to chloramphenicol and all strains were resistant to streptomycin. Resistance to HgCl2, NiSO4.6H2O and CuSO4 was observed in 83.3, 86.6 and 100% of the strains, respectively. All strains were inhibited by the presence of CoSO4. Tolerance to ethanol and variable responses to different amounts of creolin, phenol and xylol was also observed. Amplification of DNA of each of 30 isolates using repetitive primers allowed the identification of 5 groups of similar strains in BOX-PCR and 8 groups in REP-PCR. Using cloned toxin genes from B. sphaericus as probes in hybridization studies, 83% of the strains studied hybridized to the bin probe and 90% to the mtx probe. A comparison of the 30 strains by similarity matrix analysis using the data obtained in all approaches used in this study resulted in 22 groups (16 groups among the 24 high-toxicity strains) at 100% similarity, indicating a high degree of diversity among the strains tested. Some of the strains studied here, which are resistant to different stress conditions, should be considered for further ecological studies.