instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
question:
Context: Classical conditioning of the eyeblink reflex is a simple form of motor learning which depends on the integrity of the cerebellum. Acquisition of conditioned eyeblink responses is markedly reduced in patients with cerebellar disorders. Noninvasive transcranial direct current stimulation (tDCS) has been reported to modify the excitability of the cerebellar cortex.', 'The aim of the study was to assess whether acquisition of conditioned eyeblink responses (CR) is altered by cerebellar tDCS.', 'A standard delay conditioning paradigm with a 540 ms tone as conditioned stimulus (CS) coterminating with a 100 ms air puff as unconditioned stimulus (US) was used in a total of 30 healthy subjects (18 female, 12 male, mean age 23.4 ± 1.9 years). One hundred paired CS-US trials and 30 extinction CS alone trials were given. tDCS (2 mA intensity, ramp like onset) was applied over the right cerebellar hemisphere ipsilaterally to the US during the acquisition phase. Subjects were randomly assigned to three groups (n = 10) using anodal, cathodal or sham stimulation. The investigator as well as the participants was blinded to the stimulation modality.', 'CR acquisition was significantly enhanced by anodal tDCS (mean total CR incidence 73.4 ± 25.2%) and significantly reduced by cathodal stimulation (12.6 ± 17.2%) compared to sham stimulation (43.8 ± 24.1%). During anodal tDCS CR onset occurred significantly earlier, that is mean onset of responses was shifted closer to CS onset.\Question: Is acquisition of conditioned eyeblink responses modulated by cerebellar tDCS?
answer:
Acquisition and timing of conditioned eyeblink responses is modified by cerebellar tDCS in a polarity dependent manner.


question:
Context: Polycystic ovary syndrome (PCOS) is a common endocrinopathy of uncertain etiology but with strong evidence for a genetic contribution.', 'The objective of the study was to test the hypothesis that the typical polycystic ovarian morphology is a marker of inherited biochemical features in families of women with PCOS.', 'A study of probands with PCOS and their sisters.', 'Patients included 125 probands and 214 sisters. All probands had PCOS, defined by symptoms of anovulation and/or hyperandrogenism with polycystic ovaries on ultrasound. Affected sisters were defined by polycystic ovaries, regardless of symptoms, and unaffected sisters defined by normal ovarian morphology.', 'This was a clinic-based study.', 'Clinical, endocrine, and metabolic features in the various groups were compared, and estimates of broad-sense heritability were obtained using the quantitative transmission disequilibrium test.', 'Although affected sisters had fewer symptoms than probands (30% had no symptoms of PCOS), serum testosterone, androstenedione, LH, and fasting insulin and insulin sensitivity were similar in the two groups with polycystic ovaries but significantly different from those in unaffected sisters or controls. We observed moderate to high heritabilities for all traits studied in affected sister pairs, whereas heritabilities calculated from discordant siblings were substantially lower.\Question: Is ovarian morphology a marker of heritable biochemical traits in sisters with polycystic ovaries?
answer:
These data provide further evidence for a genetic basis of PCOS. The high heritability of biochemical features in probands and affected sisters, despite wide variation in symptoms, shows that not only are these biochemical traits strongly influenced by genetic factors but also, importantly, that polycystic ovarian morphology is an index of inherited traits in families with PCOS.


question:
Context: Krüpple-like factor 5 (KLF5) is a transcription factor that is highly expressed in the proliferative compartment of the intestinal crypt. There, it is thought to regulate epithelial turnover and homeostasis.', 'In this study, we sought to determine the role for Klf5 in the maintenance of cellular proliferation, cytodifferentiation, and morphology of the crypt-villus axis.', 'Tamoxifen-induced recombination directed by the epithelial-specific Villin promoter (in Villin-CreERT2 transgenic mice) was used to delete Klf5 (in Klf5 (loxP/loxP) mice) from the adult mouse intestine and analyzed by immunostaining and RT-qPCR. Control mice were tamoxifen-treated Klf5 (loxP/loxP) mice lacking Villin-CreERT2.', 'Three days after tamoxifen-induced recombination, the mitosis marker phospho-histone H3 was significantly reduced within the Klf5-mutant crypt epithelium, coincident with increased expression of the apoptosis marker cleaved-caspase 3 within the crypt where cell death rarely occurs normally. We also observed a reduction in Chromagranin A expressing enteroendocrine cells, though no significant change was seen in other secretory or absorptive cell types. To examine the long-term repercussions of Klf5 loss, we killed mice 5, 14, and 28 days post recombination and found reemerging expression of KLF5. Furthermore, we observed restoration of cellular proliferation, though not to levels seen wildtype intestinal crypts. Reduction of apoptosis to levels comparable to the wildtype intestinal crypt was also observed at later time points. Analysis of cell cycle machinery indicated no significant perturbation upon deletion of Klf5; however, a reduction of stem cell markers Ascl2, Lgr5, and Olfm4 was observed at all time points following Klf5 deletion.\Question: Is krüpple-like factor 5 required for proper maintenance of adult intestinal crypt cellular proliferation?
answer:

These results indicate that Klf5 is necessary to maintain adult intestinal crypt proliferation and proper cellular differentiation. Rapid replacement of Klf5-mutant crypts with wildtype cells and reduction of stem cell markers suggests further that Klf5 is required for self renewal of intestinal stem cells.