***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Patients with kidney stones are routinely advised to increase their fluid intake to decrease the risk of stone recurrence . However , there has been no detailed examination to determine whether the effect on recurrence varies by the type of beverage consumed . The authors conducted a prospect i ve study of the relation between the intake of 21 different beverages and the risk of symptomatic kidney stones in a cohort of 45,289 men , 40 - 75 years of age , who had no history of kidney stones .  Beverage use and other dietary information was measured by means of a semiquantitative food frequency question naire in 1986 . During 6 years of follow-up ( 242,100 person-years ) , 753 incident cases of kidney stones were documented . After adjusting simultaneously for age , dietary intake of calcium , animal protein and potassium , thiazide use , geographic region , profession , and total fluid intake , consumption of specific beverages significantly added to the prediction of kidney stone risk ( p < 0.001 ) . After mutually adjusting for the intake of other beverages , the risk of stone formation decreased by the following amount for each 240-ml ( 8-oz ) serving consumed daily : caffeinated coffee , 10 % ( 95 % confidence interval 4 - 15 % ) ; decaffeinated coffee , 10 % ( 3 - 16 % ) ; tea , 14 % ( 5 - 22 % ) ; beer , 21 % ( 12 - 30 % ) ; and wine , 39 % ( 10 - 58 % ) . For each 240-ml serving consumed daily , the risk of stone formation increased by 35 % ( 4 - 75 % ) for apple juice and 37 % ( 1 - 85 % ) for grapefruit juice . The authors conclude that beverage type may have an effect on stone formation that involves more than additional fluid intake alone 1 . Eight recurrent renal stone-forming patients were housed in a metabolic ward and fed on a low ( LPD ) and a high ( HPD ) animal protein diet , which were isoenergetic . Metabolic studies were made after 2 weeks on each diet . 2 . There was a 90 % increase in urinary urate on HPD compared with LPD , whereas serum urate did not change consistently . 3 . The urinary acid excretion increased by 200 % , including a 100 % increase in ammonium ion excretion . A fall in urine pH by 0.9 unit was also seen . 4 . The calculated ion activities of the urines revealed a profound increase in the uric acid supersaturation , from undersaturation to supersaturation , and in some cases even surpassing the formation product ratio . The ammonium urate supersaturation also increased . The sodium urate supersaturation was unchanged , despite an induced natriuresis . 5 . The risk of forming uric acid or ammonium urate crystals or stones in the urine was increased on a high protein diet , whereas the risk of forming sodium urate crystals was no greater than on a low protein diet . 6 . As uric acid and ammonium urate crystals under certain conditions may adsorb a macromolecular fraction of the human urine , which inhibits calcium oxalate crystal growth , it is proposed that this mechanism , along with a decrease in urine pH , may also interfere with the inhibitory activity of calcium oxalate crystal growth and aggregation BACKGROUND A high dietary calcium intake is strongly suspected of increasing the risk of kidney stones . However , a high intake of calcium can reduce the urinary excretion of oxalate , which is thought to lower the risk . The concept that a higher dietary calcium intake increases the risk of kidney stones therefore requires examination . METHODS We conducted a prospect i ve study of the relation between dietary calcium intake and the risk of symptomatic kidney stones in a cohort of 45,619 men , 40 to 75 years of age , who had no history of kidney stones .  Dietary calcium was measured by means of a semiquantitative food-frequency question naire in 1986 . During four years of follow-up , 505 cases of kidney stones were documented . RESULTS After adjustment for age , dietary calcium intake was inversely associated with the risk of kidney stones ; the relative risk of kidney stones for men in the highest as compared with the lowest quintile group for calcium intake was 0.56 ( 95 percent confidence interval , 0.43 to 0.73 ; P for trend , < 0.001 ) . This reduction in risk decreased only slightly ( relative risk , 0.66 ; 95 percent confidence interval , 0.49 to 0.90 ) after further adjustment for other potential risk factors , including alcohol consumption and dietary intake of animal protein , potassium , and fluid . Intake of animal protein was directly associated with the risk of stone formation ( relative risk for men with the highest intake as compared with those with the lowest , 1.33 ; 95 percent confidence interval , 1.00 to 1.77 ) ; potassium intake ( relative risk , 0.49 ; 95 percent confidence interval , 0.35 to 0.68 ) and fluid intake ( relative risk , 0.71 ; 95 percent confidence interval , 0.52 to 0.97 ) were inversely related to the risk of kidney stones . CONCLUSIONS A high dietary calcium intake decreases the risk of symptomatic kidney stones The study was performed to compare the efficacy of a herbal plant , Orthosiphon gr and iflorus ( OG ) , and the drug sodium potassium citrate ( SPC ) in treatment of renal calculi . Forty-eight rural stone formers identified by ultrasonography were recruited and r and omly assigned to two treatment groups ( G1 and G2 ) . For a period up to 18 months , subjects in G1 received 2 cups of OG tea daily , each tea cup made from an OG tea bag ( contained 2.5 g dry wt ) , and G2 received 5 - 10 g of granular SPC in solution divided into three times a day . Once every 5 to 7 weeks , subjects were interviewed , given an additional drug supply , administered a kidney ultrasound and had spot urine sample s collected for relevant biochemical analysis . From the recorded ultrasound images , rates of stone size reduction per year ( ROSRPY ) were calculated . The mean ROSRPY was 28.6+/-16.0 % and 33.8+/-23.6 % for G1 and G2 , respectively . These two means were not significantly different . ROSRPY values of G1 and G2 were combined and divided into three levels : Level A ( ROSRPY > mean + 0.5 SD ) , Level M ( ROSRPY = mean + /- 0.5 SD ) and Level B ( ROSRPY < mean - 0.5 SD ) . Dissolution of stones was least in Level B which was related to higher excretions of Ca and uric acid in the urine . After treatment , 90 % of the initial clinical symptoms ( ie back pain , headaches and joint pain ) were relieved . Fatigue and loss of appetite were observed in 26.3 % of G2 subjects . Our study indicates that treatment of renal calculi with OG tea is an alternative means of management . Further investigation is needed to improve dissolution of stones with a low ROSRPY Phyllanthus niruri is a plant used for years in Brazil to treat urinary calculi . We prospect ively evaluated the effect of P. niruri intake on 24 h urinary biochemical parameters in an attempt to assess its in vivo effect in calcium stone forming ( CSF ) patients . A total of 69 CSF patients ( 39 males and 30 females , 38±8 years old ) were r and omized to take either P. niruri ( n=33 ) ( 450 mg capsules , td ) or placebo ( n=36 ) for 3 months . Blood calcium , uric acid , citrate , magnesium , oxalate , sodium and potassium were determined at baseline and at the end of the study . A subset analysis was made in patients classified according to the presence of metabolic abnormalities ( hypercalciuria , hyperuricosuria , hyperoxaluria , hypocitraturia and hypomagnesiuria ) . Overall , there were no significant differences in the mean values of urinary parameters between the urine sample s before and after P. niruri intake , except for a slight reduction in mean urinary magnesium  after P. niruri , which was within the normal range . However , in the subset analysis , we observed that P. niruri induced a significant reduction in the mean urinary calcium in hypercalciuric patients ( 4.8±1.0 vs 3.4±1.1 mg/kg/24 h , P<0.05 ) . In this short-term follow-up , no significant differences in calculi voiding and /or pain relief between the groups taking P. niruri or the placebo were detected . Our data suggest that P. niruri intake reduces urinary calcium based on the analysis of a subset of patients presenting with hypercalciuria . Larger trials including primary hypercalciuric stone formers should be performed in order to confirm these findings and to determine the possible clinical consequences of urinary calcium reduction during P. niruri administration We evaluated the possible effects of a calcium entry blocking agent “ verapamil ” on new stone formation and /or regrowth of residual fragments  after shock wave lithotripsy ( SWL )  during long-term follow-up ( > 30 months ) and compared the results with the success rates of adequate fluid intake . A total of 70 patients treated with SWL  were r and omly divided into three different groups , in the first two of which the patients received different preventive measures with respect to stone recurrence and /or regrowth . While 25 patients received a calcium channel blocking agent , verapamil hydrochloride , beginning 3 days before SWL and continued 4 weeks after the procedure , an additional 25 patients were put in an enforced fluid intake program and the remaining 20 patients received no specific medication and /or measure apart from close follow-up . Patients were followed regularly with respect to the clearance/regrowth of the residual fragments and that of new stone formation during long-term follow-up ( within a mean follow-up of 30.4 months ) . The overall stone recurrence rate was 14 % ( 10/70 ) . Of the patients who became stone free ( 12/25 , 48 % ) in group I , only one patient ( 1/12 , 8.3 % ) showed a new stone formation during long-term follow-up . The figure was 40 % ( 4/10 ) in group II patients and 55 % ( 5/9 ) in group III patients receiving no specific medication . Regarding the residual stone fragments ( < 5 mm ) after SWL , again high fluid intake was found to be the most effective on stone regrowth rates ( 2/13 , 15.3 % ) . Patients treated with verapamil also had acceptable regrowth rates ( 3/15 , 20 % ) . Finally , verapamil treatment significantly improved the clearance of residual fragments ; while 7 out of 15 patients with residual fragments passed these particles successfully , ( 46.5 % ) in this group ; these figures were 46 % ( 6/13 ) and 18 % ( 2/13 ) in the remaining groups . Residual fragments located in lower calyces demonstrated a poor clearance rate with higher regrowth rates .  Verapamil administration was found to be effective enough to limit the regrowth of residual fragments and also to facilitate residual fragment clearance after SWL . Patients receiving this medication seemed to pass the retained fragments easily in a shorter time than the others Low protein diets are commonly prescribed for patients with idiopathic calcium nephrolithiasis , who account for > 80 % of new diagnoses of kidney stones . This dietary advice is supported by metabolic studies and epidemiologic observational studies but has not been evaluated in a controlled trial . Using 1983 - 1985 data from three Northern California Kaiser Permanente Medical Centers , the authors r and omly assigned 99 persons who had calcium oxalate stones for the first time to a low animal protein , high fiber diet that contained approximately 56 - 64 g daily of protein , 75 mg daily of purine ( primarily from animal protein and legumes ) , one-fourth cup of wheat bran supplement , and fruits and vegetables . Intervention subjects were also instructed to drink six to eight glasses of liquid daily and to maintain adequate calcium intake from dairy products or calcium supplements . Control subjects were instructed only on fluid intake and adequate calcium intake . Both groups were followed regularly for up to 4.5 years with food frequency question naires , serum and urine chemistry analysis , and abdominal radiography ; and they were urged to comply with dietary instructions . In the intervention group of 50 subjects , stones recurred in 12 ( 7.1 per 100 person-years ) compared with two ( 1.2 per 100 person-years ) in the control group ; both groups received a mean of 3.4 person-years of follow-up ( p = 0.006 ) . After adjustment for possible confounding effects of age , sex , education , and baseline protein and fluid intake , the relative risk of a recurrent stone in the intervention group was 5.6 ( 95 % confidence interval 1.2 - 26.1 ) compared with the control group . The authors conclude that advice to follow a low animal protein , high fiber , high fluid diet has no advantage over advice to increase fluid intake alone To assess , in a multicentre prospect i ve r and omized study , the effectiveness of specific nonmedical prophylaxis and nonspecific dietary prophylaxis in patients treated after experiencing their first idiopathic calcium‐containing kidney stone PURPOSE We define the role of urine volume as a stone risk factor in idiopathic calcium stone disease and test the actual preventive effectiveness of a high water int 
    Output:
    
High fluid intake decreased risk of recurrent nephrolithiasis .
Reduced soft drink intake lowered risk in patients with high baseline soft drink consumption .
Data for other dietary interventions were inconclusive , although limited data suggest possible benefit from dietary calcium