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.

Ex Input:
Context: The blasticidin S resistance gene (bsr) is a selectable marker used for gene transfer experiments. The bsr gene encodes for blasticidin S (BS) deaminase, which has a specific activity upon BS. Therefore, its expression is supposed to be harmless in cells. The work reported on herein consisted of experiments to verify a possible toxicity of bsr on mammalian cells, which include several cell lines and primary cultures.', 'Murine keratinocyte BALB/MK and human primary keratinocyte cells transduced with the retroviral vector LBmSN, which has an improved expression system of bsr, namely bsrm, died in five days after the transduction. Meanwhile the control vector LBSN, which expresses bsr, did not provoke cell death. The lethal activity of bsrm was observed only in human keratinocytes and BALB/MK cells among the cell types tested here. Death appears to be mediated by a factor, which is secreted by the BALB/MK transduced cells.\Question: Is over expression of the selectable marker blasticidin S deaminase gene toxic to human keratinocytes and murine BALB/MK cells?

Ex Output:
By our study we demonstrated that the expression of bsrm gene is toxic to human keratinocytes and BALB/MK cells. It is likely over expression of BS deaminase gene is responsible for the death.


Ex Input:
Context: The aim of this study was to evaluate the effect of local injection of vasopressin on blood loss and secondary impact on complications during cesarean section in patients with placenta previa.', 'We retrospectively reviewed the medical records of all patients diagnosed with placenta previa admitted to our hospital. Two consecutive periods were compared. During period B, 59 patients underwent the local injection of a vasopressin solution (4 U in 20 mL of saline) into the placental implantation site after placental delivery. During period A, 50 patients underwent cesarean section without vasopressin injection, and were analyzed as a control group. The estimated blood loss was recorded, as were the complications during surgery. In addition, the expression of the vasopressin V1α receptor in uterine smooth muscle was evaluated by immunohistochemistry.', 'The mean estimated blood loss was significantly lower in the vasopressin group than in the control group. There were no statistically significant differences with surgical complications. The vasopressin V1α receptor was highly expressed in smooth muscle cells in the lower segment of the uterine body, whereas the immunoreactivity for the oxytocin receptor was faint in the lower segment.\Question: Does local injection of vasopressin reduce the blood loss during cesarean section in placenta previa?

Ex Output:
The local injection of vasopressin into the placental implantation site significantly reduced the blood loss without increasing the morbidity.


Ex Input:
Context: Very low birth weight (VLBW) infants are at risk to develop nephrocalcinosis (NC). NC may result from spontaneous or therapy-induced imbalance between promoters and inhibitors of crystallization in the urine. However, data on "normal" urinary excretions of these parameters in VLBW infants are sparse. Therefore, we prospectively examined the urinary excretion of calcium, oxalate, uric acid, and citrate in VLBW infants during the first 8 weeks of life.', 'Urine samples were collected once weekly in 124 VLBW infants. NC appeared in 16 infants, whose data were separately analyzed. The remaining 108 infants were divided into subgroups: A, <1000 g (N = 53); and B, 1000 to 1500 g (N = 55). Random urine samples were analyzed and the results were expressed as molar creatinine ratios. Calcium/citrate and oxalate/citrate expressed the risk for calcium oxalate crystallization.', 'In group A, citrate excretion was lower at weeks 2 to 5 and 7; calcium/citrate was higher in weeks 2, 4, and 7; oxalate/citrate was higher in weeks 3, 4, 7, and 8; and calcium/creatinine ratio was higher in week 4 (P < 0.05). Citrate/creatinine ratios were low in nine infants with NC. Oxalate/creatinine and calcium/creatinine were elevated in five and calcium/citrate was increased in nine infants with NC.\Question: Is hypocitraturia one of the major risk factors for nephrocalcinosis in very low birth weight ( VLBW ) infants?

Ex Output:

Hypocitraturia is a major risk factor for NC in VLBW infants, especially in those <1000 g. The urinary excretions in VLBW infants seem to depend on birth weight, age, and clinical condition. Hence, supplementation with alkali citrate may have a beneficial effect in the prevention of NC.