An audit of forceps delivery in Trinidad.

An audit of 247 consecutive forceps deliveries during a 6-year period was undertaken in order to establish trends in recourse to this instrument, maternal complications and fetal outcome. The chief indications were prolonged second stage of labour and poor maternal effort. Our overall forceps rate of 0.81% betrays a marked divergence from the practice in metropolitan countries. Although birth injuries were a major drawback, assistance with forceps still appears to be a safer alternative than caesarean section when a problem exists which impedes spontaneous delivery in the second stage. In choosing between obstetric options, we voluntarily take one course which we dislike because the alternative is more objectionable still; the unpleasantness of the choice does not destroy its reality.

Chlorpromazine inhibits both the constitutive nitric oxide synthase and the induction of nitric oxide synthase after LPS challenge.

The effects of chlorpromazine on either the activity of mouse brain nitric oxide synthase or the induction of lung nitric oxide synthase in mice and rats were studied. Chlorpromazine inhibited the nitric oxide synthase activity in mouse brain cytosol. This effect could be reversed by adding an excess of calmodulin. In addition, chlorpromazine was able to inhibit the induction of lung nitric oxide synthase, in both species, after LPS administration. Furthermore, chlorpromazine also inhibited arginase activity in mouse lung cytosol.

The spectrum of acute renal failure in a developing country - abstract

Acute renal failure (ARF) has had an unchanged mortality of greater than 50 percent for the past 30 years, despite advances in critical care management. The aetiologies, complications, and prognosis have been well described in the literature from developed countries. A 30-month prospective survey of all cases of ARF seen at the Princess Margaret Hospital since January 1986 was undertaken. Of a total of 1,014 cases, 98 were analyzed; and the principal findings were the following. Sepsis was the leading cause identified in 47 patients (48 percent); Hypoperfusion-related states occurred in 41 patients (42 percent); Nephrotoxins were identified in 18 patients (18 percent); Vasculatic disease accounted for 15 patients, and Obstructive uropathy was the major factor in 11 patients. Nearly 50 percent of the patients had non-oliguric ARF. The mortality was 36.1 percent, and 67.3 percent in the non-oliguric and oliguric groups, respectively. Seven patients were classified as having died due to renal failure, and the overall combined mortality of all the patients was 51 percent. Of the 98 patients, 21 had complete recovery (21 percent); 23 patients had renal insufficiency (24 percent); and 47 patients (48 percent) were classified as non-renal deaths. A new entity of Cocaine-induced Rhabdomyolysis is described in 2 patients and the pathogenesis discussed. This survey indicates that the mortality of 55 percent in this developing country is comparable to figures reported from more advanced metropolitan countries (AU)

The PermCath for temporary vascular access - abstract

This paper is a report of one year's experience with the PermCath central venous access dialysis catheter in the Bahamas. The PermCath was employed for temporary access in patients requiring chronic haemo-dialysis while awaiting permanent access sites. PermCaths were inserted via internal or external jugular vein cut-down under local anaesthesia. Fifteen catheters were inserted in 13 patients. One patient had three PermCaths. The 15 PermCaths were in situ for a total of 1,224 patient days and 385 dialysis episodes. The catheters were in situ for a range of 3 to 155 days, an average of 81.5 days per patient. Six patients had a catheter in situ longer than four months. Three PermCaths were removed because of sepsis and one for occlusion. There were no exit site infections or clinical thrombosis. It is concluded that PermCaths can be used safely for long term vascular access, with minimal morbidity and their use is recommended if temporary access is required for longer than four weeks (AU)

Temporary vascular access for chronic haemodialysis: the Bahamian experience - abstract

We report our experience with the Shiley Double Lumen (SDL) and Permacath (PC) central venous access dialysis catheters during the period May 1986 to August 1988. The SDL Catheter study was confined to all patients selected for chronic dialysis and awaiting vascular access by a visiting access surgeon; patients receiving A-V shunts or peritoneal dialysis were excluded. PC was introduced in December, 1987 as an alternative to SDL. SDLs were inserted by standard percutaneous Seldinger technique in the dialysis unit, and PC via an internal jugular vein cutdown under local anaesthesia. Of the group of patients for chronic renal dialysis on temporary SDL access, the 21 patients who eventually had permanent vascular access were reviewed. No patients failing to achieve permanent vascular access died or were discontinued from dialysis due to complications of SDL cannulation. The 21 patients received 40 SDL cannulations (17 right subclavian vein, 21 left subclavian and 2 right femorals) for a total of 1,170 patient days and 393 haemodialysis episodes. SDLs were resited if there was sepsis, luminal thrombosis or clinical signs of subclavian vein thrombosis. One patient was carried for 215 days on SDL catheterizations. The longest site cannulated was 139 days. Seven patients received PC for a total of 720 patient days and 240 dialysis. Four catheters were removed after permanent access was established, 1 after sepsis and 2 remain in situ. We conclude that SDL and PC catheters can be safely used over an extended period for temporary dialysis on an outpatient basis without compromising future permanent access. This is particularly suited for geographical areas lacking a permanent vascular access surgeon (AU)

Hydrogenase activity in Azospirillum brasilense is inhibited by nitrite, nitric oxide, carbon monoxide, and acetylene.

Nitrite, NO, CO, and C2H2 inhibited O2-dependent H2 uptake (H3H oxidation) in denitrifying Azospirillum brasilense Sp7 grown anaerobically on N2O or NO3-. The apparent Ki values for inhibition of O2-dependent H2 uptake were 20 microM for NO2-, 0.4 microM for NO, 28 microM for CO, and 88 microM for C2H2. These inhibitors also affected methylene blue-dependent H2 uptake, presumably by acting directly on the hydrogenase. Nitrite and NO inhibited H2 uptake irreversibly, whereas inhibition due to CO was easily reversed by repeatedly evacuating and backfilling with N2. The C2H2 inhibition was not readily reversed, partly due to difficulty in removing the last traces of this gas from solution. The NO2- inhibition of malate-dependent respiration was readily reversed by repeatedly washing the cells, in contrast to the effect of NO2- on H2-dependent respiration. These results suggest that the low hydrogenase activities observed in NO3(-)-grown cultures of A. brasilense may be due to the irreversible inhibition of hydrogenase by NO2- and NO produced by NO3- reduction.

Uptake hydrogenase activity in denitrifying Azospirillum brasilense grown anaerobically with nitrous oxide or nitrate.

zospirillum brasilense Sp7 was grown anaerobically with N2O as the terminal electron acceptor and NH4Cl as the nitrogen source. Hydrogen uptake activity (O2-dependent H3H oxidation) was expressed in the presence and absence of 5% H2; it reached its maximum in late logarithmic phase as the malate became limiting. This activity was very stable in stationary phase, even in the absence of exogenous H2, compared with microaerobically grown cultures; this supports the hypothesis that the exclusion of O2 is critical for maintaining the integrity of the H2 uptake system in this organism. Oxygen, as well as methylene blue and N2O, supported H2 uptake, indicating the presence of electron transport components leading to O2 in anaerobically grown A. brasilense. Nitrite (0.5 mM) inhibited H2 uptake. In cultures grown with NO3- as the terminal electron acceptor and NH4Cl as the nitrogen source, in the presence and absence of exogenous H2, only low H2 uptake activity was observed. Methylene blue, O2, N2O, NO3-, and NO2- were all capable of acting as the electron acceptor for H2 oxidation. Nitrite (0.5 mM) did not inhibit H2 uptake in NO3--grown cells, as it did in N2O-grown cells. A. brasilense appears to be one of the few organisms capable of expressing the H2 uptake system under denitrifying conditions in the absence of molecular H2.

Clinical and serological evidence of bovine babesiosis and anaplasmosis in St. Lucia.

One hundred fifty-nine Holstein calves were imported into St. Lucia from the U.S.A. An outbreak of babesiosis occurred 17 days post-arrival, and an outbreak of anaplasmosis occurred 5 months after importation. Sera obtained 3, 6, and 12 months post-importation revealed a high prevalence of IFA titres to Babesia bovis and B. Bigemina 3 months after arrival and an increase in titres to Anaplasma marginale 6 months after arrival. Sera obtained from native cattle from several places on the island indicated infection rates of 80, 65 and 64% with A. marginale, B. bigemina and B. bovis, respectively. The rapid card test only indicated a 25% prevalence of infection of native cattle by A. marginale. This low prevalence was probably due to deterioration of serological activity during shipment.

Hydrogen metabolism of Azospirillum brasilense in nitrogen-free medium.

Production of H2 by Azospirillum brasilense under N2-fixing conditions was studied in continuous and batch cultures. Net H2 production was consistently observed only when the gas phase contained CO. Nitrogenase activity (C2H2 reduction) and H2 evolution (in the presence of 5% CO) showed a similar response to O2 and were highest at 0.75% dissolved O2. Uptake hydrogenase activity, ranging from 0.3 to 2.5 mumol H2/mg protein per hour was observed in batch cultures under N2. Such rates were more than sufficient to recycle nitrogenase-produced H2. Tritium-exchange assay showed that H2 uptake was higher under Ar than under N2. Uptake hydrogenase was strongly inhibited by CO and C2H2. Cyclic GMP inhibited both nitrogenase and uptake hydrogenase activities.

Effect of oxygen and nitrate on nitrogen fixation and denitrification by Azospirillum brasilense grown in continuous culture.

Azospirillum brasilense was grown continuously at various levels of dissolved oxygen (O2) in a nitrogen-free medium containing malates as the carbon source. Steady-state cultures were established only at O2 concentrations less than 0.0150 atm (1 atm = 101.325 Pa) and rates of acetylene reduction (N2 fixation) and efficiencies of N2 fixation were maximal between 0.0050-0.0075 atm dissolved O2. These cultures appeared to be O2- or N2-limited. There was no evidence of a respiratory protective mechanism in this organism. Anaerobic denitrifying steady-state cultures were established with nitrate (NO3-) as the sole nitrogen source with no detectable N2 fixation. N2 fixation, but no denitrification, was observed when NO3- was decreased to 10 microgram N per millilitre at 0.003 atm dissolved O2. In samples removed from the culture vessel, either activity could be induced with a lag of approximately 120 min by incubation under appropriate conditions.