[Study of the natural killer cell activity in lung cancer patients]

A total of 50 lung CA patients and 20 normal persons as control were included in our study. We obtained lymphocytes from heparinized blood by Ficoll-Hypaque gradient method and after incubation with Cr51 labelled K562 cells at concentrations of 100: 1, 50:1, 12.5:1 for four hours, we calculated the cytotoxicity activity of NK cells. Significant impairment was noted in the comparison of NK cytotoxicity between stage III-M1 lung CA patients (n = 28) and the control group (n = 20) (E/T; 50:1, 29.55 +/- 24.20% vs 49.83 +/- 14.46%, p less than 0.001; E/T: 25:1, 10.23 +/- 7.19% vs 27.66 +/- 6.06%, p less than 0.001). 4 cases in stage I underwent surgery, the NK cytotoxicity before the operation was noted to be low, E/T: 25:1, 9%, 11%, 14% and 19% respectively. After the operation, the NK cytotoxicity was increased to 33%, 35%, 42% and 44% respectively. 3 stage I lung CA patients has continuously followed up, 2 relapsed cases had decreased NK cytotoxicity to 22% and 25%. These results indicated that the NK cytotoxicity assay was impaired in stage III-M1 lung CA and also suggested that it may act as a therapeutic guide for the results of the operation.

Early third-stage larvae of Gnathostoma hispidum in cyclops. Surface topography revealed by scanning electron microscopy

Surface structures of the early third-stage larvae were examined by scanning electron microscopy. There were hemispherical head-bulbs at the apical ends. These bulbs could be clearly distinguished from the bodies. The head-bulbs (52 X 29 micron) had four transverse rows of sharp hooklets. The number of hooklets in each row was 37, 36, 38, and 43, posteriorly. The larvae posessed a pair of lateral lips in the head-bulb. Each of the lips had two labial papillae and an amphid between the papillae. Small unidentate cuticular spines were present along the entire length of larvae on their transverse striations. The number of these cuticular striations was 175-217. A pair of cervical papillae and an excretory pore were present on the anterior part of the body. Another pair of papillae was detected laterally on the posterior one-third of the body. The shape of the posterior body papillae resembled that of cervical papillae. The cuticular spines were absent around the anus.

A new disposable microvascular double clip

A new disposable microvascular double clip made of polycarbonate has been designed. In order to investigate whether or not the clip causes vascular damage, experiments were conducted with scanning electron microscopy and light microscopy, using the common carotid arteries of Fischer rats. The study revealed that the new clip did not produce any damage to the arterial wall. The clip has also been used in 30 clinical cases, with generally good results. The new microvascular clip is economical, atraumatic to the vascular wall, and is always in the best condition, because of its disposability. The device is very useful for both laboratory and clinical microvascular surgery.

Effects of verapamil alone and with captopril on blood pressure and bilateral renal function in Goldblatt hypertensive rats

The effects of verapamil infusion alone and superimposed with captopril on arterial pressure and bilateral renal function were evaluated in 21 two-kidney, one-clip Goldblatt hypertensive rats and in 13 control rats. Verapamil significantly decreased arterial pressure of both hypertensive and control rats. Addition of captopril further reduced arterial pressure in hypertensive rats only. There were significant increases in glomerular filtration rate (GFR), urine flow and absolute and fractional excretory rates of sodium and potassium in the non-clipped kidney. In contrast, these renal indices decreased in the clipped kidney. Superimposed captopril during verapamil infusion did not significantly change function of the non-clipped kidney but further depressed function of the clipped kidney. In control rats, no significant change in GFR occurred in response to drugs. Renal excretion of water and sodium, but not potassium, increased after verapamil. However, the diuresis and natriuresis were less pronounced than those seen in the non-clipped kidney of hypertensive rats. There was a proportionate increase in osmolar clearance and free water reabsorption rate in the non-clipped kidney and the normal kidney. The linear relationship did not change after verapamil infusion. The results suggest that verapamil enhances the excretory function of the non-clipped kidney of Goldblatt hypertensive rats via increased GFR and decreased tubular reabsorption in the proximal and/or distal tubules despite its hypotensive action.

Antihypertensive and bilateral renal responses to nifedipine in 2-kidney, 1-clip, Goldblatt hypertensive rats

Experiments were performed to assess the effects of nifedipine, a calcium channel blocker, on the blood pressure and bilateral renal function in 2-kidney, 1-clip, Goldblatt hypertensive rats. Hypertensive rats were prepared 4 weeks prior to the acute experiments, Nifedipine was administered intravenously into hypertensive (n = 11) and control (n = 12) rats under pentobarbital anesthesia. In hypertensive rats, nifedipine (0.02 mg/kg) reduced the mean arterial pressure from 151 +/- 5 to 135 +/- 5 mm Hg. Despite the fall of arterial pressure, there were significant increases in glomerular filtration rate (GFR) from 1.36 +/- 0.13 to 1.80 +/- 0.22 ml/min, urine flow from 7.8 +/- 1.6 to 17.0 +/- 3.8 microliter/min, and excretions of absolute and fractional sodium from 1.07 +/- 0.43 mu Eg/min and 0.50 +/- 0.15% to 2.80 +/- 0.73 mu Eq/min and 0.92 +/- 17%, respectively, in the nonclipped kidney. No significant changes in these renal indices occurred in the clipped kidney. In control rats, administration of nifedipine (0.04 mg/kg) also significantly decreased the arterial pressure from 119 +/- 4 to 110 +/- 4 mm Hg. There were slight but insignificant increases in GFR and renal excretion of sodium and water. In both groups, nifedipine produced proportionate increases in osmolar clearance and free water reabsorption. These results suggest that nifedipine enhances glomerular filtration and suppresses the reabsorption of sodium and water by the proximal tubule and/or distal nephron segments. The resulting increase in excretory function of the nonclipped kidney may, in part, contribute to the blood pressure-lowering effect of this drug.

Nephron responses to converting enzyme inhibition in non-clipped kidney of Goldblatt hypertensive rat at normotensive pressures

To evaluate the effects of angiotensin converting enzyme inhibition (SQ 20881, CEI) on superficial nephron function of the non-clipped kidney in Goldblatt hypertensive rats in the absence of alterations in renal arterial pressure, control renal arterial pressure (RAP) was reduced first to the range generally obtained during CEI (124 +/- 4 mm Hg). RAP was maintained during the CEI period by adjustment of a suprarenal aortic clamp. At the reduced RAP, whole kidney and single nephron glomerular filtration rates (GFR) were reduced from the hypertensive levels and were lower than the measurements in normotensive control rats. During CEI, whole kidney GFR and single nephron GFR increased by 55 and 42%, respectively. There were decreases in absolute as well as fractional proximal reabsorption rates. In the intermediate nephron segment, fractional reabsorption was decreased, but absolute fluid reabsorption increased in proportion to the increased delivery rate. Proximal tubule and peritubular capillary hydrostatic pressures increased significantly during CEI also. These results indicate that an increased activity of the renin-angiotensin system occurring in Goldblatt hypertensive rats subjected to aortic constriction exerts effects to lower GFR and increase proximal reabsorption rate. The concomitant superficial nephron and whole kidney GFR responses to CEI when arterial pressure was maintained suggests that the pre-existing levels of angiotensin exerted similar influences on the total nephron population.

Angiotensin-mediated alterations in nephron function in Goldblatt hypertensive rats

The present study was performed to evaluate superficial nephron responses of the nonclipped kidney to angiotensin I converting enzyme inhibitor (CEI) (SQ 20,881, 3 mg . kg-1 . h-1) in two-kidney, one-clip Goldblatt hypertensive (GH) rats. Late proximal and early distal tubule collections were obtained before and during CEI. Significant increases in glomerular filtration rate, urine flow, sodium excretion, proximal and distal tubule flow rates, and single nephron glomerular filtration rate (from 24.6 +/- 1.7 to 27.5 +/- 1.6 nl/min) occurred despite reductions in arterial blood pressure (from 160 +/- 5 to 137 +/- 6 mmHg) during CEI. Proximal tubule absolute and fractional reabsorption of fluid, chloride, and total solute decreased significantly. In the nephron segment between the two collection sites, there were increases in absolute but decreases in fractional reabsorption. At the distal tubule level, fractional reabsorption but not absolute reabsorption decreased significantly. Proximal and distal tubule hydrostatic pressures increased significantly while peritubular capillary pressure decreased slightly. Responses following inhibition of angiotensin II formation suggest that there exists an angiotensin II-mediated enhancement in tubular reabsorption in the nonclipped kidney of Goldblatt hypertensive rats.

Effects of saralasin infusion on bilateral renal function in two-kidney, one-clip Goldblatt hypertensive rats

1. Previous studies have shown that administration of converting enzyme inhibitor (CEI, SQ 20 881) to two-kidney, one-clip Goldblatt hypertensive (GH) rats clipped for 3-4 weeks resulted in marked increases in glomerular filtration rate (GFR), water and sodium excretion by the non-clipped kidneys. The clipped kidneys exhibited reduced function that was due, in part, to the reductions in arterial pressure. To evaluate further the hypothesis that the renal responses to CEI were due primarily to the inhibition of angiotensin II rather than other factors, we infused the angiotensin II competitive blocker, saralasin, into GH rats under sodium pentobarbital anaesthesia and examined renal haemodynamics and excretory function of each kidney before and during saralasin infusion and after cessation of saralasin infusion. 2. Saralasin reduced mean arterial blood pressure from 164 +/- 4 to 124 +/- 4 mmHg. Despite the profound fall of arterial pressure, significant increases in renal blood flow from 5.82 +/- 0.22 to 9.15 +/- 0.76 ml/min and glomerular filtration rate from 1.46 +/- 0.10 to 2.18 +/- 0.14 ml/min were observed in the non-clipped kidneys. Renal vascular resistance decreased from 2.34 (+/- 0.14) x 10(5) to 1.17 (+/- 0.19) x 10(5) kPa 1(-1) s [2.34 (+/- 0.14) x 10(6) to 1.17 (+/- 0.19) x 10(6) dyn s cm-5]. Also, concomitant diuresis and kaliuresis and a delayed natriuresis occurred. 3. The clipped kidneys exhibited reductions in renal blood flow, GFR and excretory function during saralasin infusion. 4. Normal rats receiving the identical dose of saralasin responded with a slight but significant decrease in arterial pressure. The increase in renal blood flow and GFR were less than those observed in the non-clipped kidneys of hypertensive rats. 5. These data provide further support to the hypothesis that an angiotensin II-mediated elevation in renal vascular resistance and impairment of renal function exist in the non-clipped kidneys of GH rats.

Attenuated pressure natriuresis in hypertensive rats

We studied the isolated blood-free perfused nonclipped kidneys from the 2-kidney Goldblatt hypertensive rat model (GHR) to evaluate intrinsic excretory responses to changes in perfusion pressure. We examined kidneys from 10 control rats (in vivo systolic BP 110 +/- 3.6 mm Hg), from 9 rats with nonmalignant hypertension (HBP) (in vivo systolic BP 158 +/- 6.5 mm Hg), and from 5 rats with malignant HBP (in vivo systolic BP 183 +/- 6.4 mm Hg). We found that at all levels of perfusion pressure, the renal vascular resistances were significantly higher and glomerular filtration rate (GFR) lower in kidneys from hypertensive rats than in kidneys from control rats. Kidneys from hypertensive rats had lower urinary excretion of sodium (UNaV) and urine flow than kidneys from control rats at all levels of pressure above 100 mm Hg. The most striking differences in all functional parameters were noted in kidneys from rats with malignant HBP. Kidneys from both hypertensive and control rats failed to show changes in vascular resistance in response to Saralasin. We conclude that the nonclipped kidney in GHR exhibits a blunted natriuresis in response to elevated perfusion pressure which occurs in the absence of angiotensin II (AII) and renin substrate. This diminished pressure natriuresis may be caused partly by the lower GFR and by reduced pressure transmission due to greater renal vascular resistance and thus may be partially responsible for the maintenance of the hypertensive state.

Influence of converting enzyme inhibition on renal hemodynamics and glomerular dynamics in sodium-restricted dogs

Clearance and micropuncture experiments were performed to evaluate the influence of converting enzyme inhibition (CEI) (SQ 14,225) on renal hemodynamics, glomerular filtration rate (GFR), segmental vascular resistances, and superficial nephron function in anesthetized sodium restricted dogs. In one series (n = 8), renal blood flow (RBF) and GFR exhibited a high degree of autoregulatory efficiency when renal arterial pressure (RAP) was reduced from 126 +/- 5 to 86 +/- 1 mm Hg. With RAP maintained at the reduced level, CEI elicited increases in RBF (3.9 +/- 0.3 to 5.8 +/- 0.5 ml/min per g kw) and GFR (0.81 +/- 0.03 to 0.94 +/- 0.04 ml/min per g kw). With return of RAP to spontaneous levels during continued CEI, RBF and GFR autoregulatory efficiency was maintained, and was similar to that observed in control dogs subjected to the same procedures (n = 5). In the micropuncture experiments (n = 12), RAP was maintained at the reduced level (87.5 +/- .9 mm Hg), and measurements were made before and during CEI. Proximal tubule pressure, peritubular capillary pressure, stop flow pressure, and single nephron GFR (SNGFR) increased significantly. Regression analysis suggested that the increases in SNGFR were associated with small increases in the filtration coefficient. CEI reduced preglomerular resistance by 29% to 35% and efferent arteriolar resistance by 24% to 32%. These results indicate that the increased activity of the renin-angiotensin system that occurs during salt restriction exerts approximately equivalent vasoconstrictor influences on both preglomerular and postglomerular vascular resistance elements.

Impaired renal blood flow and cortical pressure autoregulation in contralateral kidneys of Goldblatt hypertensive rats

Experiments were conducted on two-kidney, one clip renal vascular hypertensive rats to assess the ability of the kidney contralateral to renal vascular stenosis to autoregulate renal blood flow (RBF), glomerular filtration rate (GFR), and hydrostatic pressures in cortical structures during conditions of acutely reduced renal arterial blood pressure (BP). When observed at their respective, spontaneous BPs, RBF and GFR were not different in the contralateral kidneys of the hypertensive rats (n = 11) compared to normal animals (n = 7). However, the contralateral kidneys exhibited a significantly higher renal vascular resistance (RVR), 28.9 +/- 2.8 mm Hg . min/ml than the control animals, 23.1 +/- 1.5 mm Hg . min/ml. At spontaneous BP (169 +/- 5 mm Hg), urine flow, absolute and fractional sodium excretion, and absolute and fractional potassium excretion were all significantly greater in the contralateral kidneys of hypertensive rats than in kidneys of normal rats. Hydrostatic pressures in cortical structures were similar in the two groups. When BP was reduced acutely, the kidney contralateral to the renal artery stenosis achieved only small decreases in RVR that failed to allow RBF, GFR, or cortical pressures to be maintained. In contrast, normal rats efficiently autoregulated RBF and GFR. In addition, hydrostatic pressures in proximal tubules, distal tubules, and first order peritubular capillaries were maintained during reductions in BP to as low as 100 mm Hg. Urine flow and electrolyte excretion decreased to a greater extent in the hypertensive kidneys, such that at comparable BP these indices of excretory function were not different in the two groups. These observations indicate that the capacity of the contralateral kidney to maintain hemodynamic and glomerular function at reduced BP is compromised severely and suggest the possibility that the impaired autoregulatory capability may contribute to the maintenance of hypertension observed in this model.

Impaired autoregulatory responses in contralateral kidneys of two-kidney, one-clip hypertensive rats

1. Micropuncture and clearance experiments in two-kidney, one-clip renal vascular hypertensive rats examined the ability of the kidney contralateral to renal vascular stenosis to maintain renal function during conditions of reduced renal arterial blood pressure. 2. At their respective spontaneous blood pressures, renal vascular resistance was higher and glomerular filtration rate (GFR) and renal blood flow were not different in the contralateral kidneys of the hypertensive rats (170 +/- 5 mmHg) compared with normal animals (129 +/- 1 mmHg). Urine flow and absolute and fractional excretion of electrolyte were greater from the kidneys of the hypertensive animals. However, pressures in cortical structures were similar in the two groups. 3. As blood pressure was reduced acutely, the kidney contralateral to the renal artery stenosis achieved only small decreases in renal vascular resistance that failed to allow GFR, renal blood flow or pressures in cortical structures to be maintained. In contrast, normal rats efficiently autoregulated renal vascular resistance to allow GFR, renal blood flow and cortical pressures to be unchanged as blood pressure was altered between 130 and 115 mmHg. Urine flow and electrolyte excretion decreased to a greater extent in the hypertensive kidneys; at comparable blood pressure these indices of excretory function were not different in the two groups. 4. These observations indicate that the contralateral kidney can maintain normal haemodynamic and glomerular function only at elevated blood pressure and suggest the possibility that the impaired capacity to autoregulate renal resistances may contribute to the maintenance of hypertension observed in this model.

Japanese encephalitis virus surveillance in the Taipei area, Taiwan in 1978

Attempts were made to isolate Japanese encephalitis virus from mosquitoes collected with three light traps operated twice a week at three sentinel pigpens in the Taipei area from May to Oct. 1978. A total of 6,549 mosquitoes trapped alive were processed in 283 pools. Suspensions were inoculated into Aedes albopictus cell cultures and into suckling mice. A total of 19 JE virus isolates were made; 12 from pools of Cx. tritaeniorhynchus, 6 from Cx. annulus and one from Cx. quinquefaciatus. Sindbis virus was isolated for the first time in Taiwan from a pool of Cx. tritaeniorhynchus. More isolates were made from mosquito cell cultures (20) than by mouse inoculation (6). Positive isolations of JE virus by mouse inoculation were all from the mosquitoes obtained during an 11 day period from 20 to 30 June 1978 when all six sentinel pigs were viremic. This study shows the decided advantage of the use of mosquito-cell cultures over that of mice.

Japanese encephalitis virus in Northern Taiwan, 1969-1973

Sentinel pigs were bled and mosiquitoes were collected for isolation of Japanese encephalitis virus (JEV) between 1969 and 1973 in a rural area of northern Taiwan which reported a high annual incidence of human cases. The study site included a farmyard, schools, a bat cave, rice paddies and a heronry. Although Culex annulus was collected in every month of the year, isolations were made only in midsummer and only from Culex annulus and (once) from Culex tritaeniorhynchus. These isolates were usually collected from pig-related sources. Human cases in the vicinity of the study site were reported 3 to 6 weeks following the initial isolations from sentinel pigs. Isolations were made only for 4 to 8 weeks each summer. The isolation of JEV was not related to the availability of susceptible pigs or the spring or summer peaks in prevalence of Culex annulus. Despite periodic draining of rice paddies and the application of insecticides, sufficient numbers of Culex annulus were available to support transmission of JEV in each year of the study.