External aluminium supply regulates photosynthesis and carbon partitioning in the Al-accumulating tropical shrub Melastoma malabathricum

Aluminium (Al) is toxic to most plants, but recent research has suggested that Al addition may stimulate growth and nutrient uptake in some species capable of accumulating high tissue Al concentrations. The physiological basis of this growth response is unknown, but it may be associated with processes linked to the regulation of carbon assimilation and partitioning by Al supply. To test alternative hypotheses for the physiological mechanism explaining this response, we examined the effects of increasing Al concentrations in the growth medium on tissue nutrient concentrations and carbon assimilation in two populations of the Al-accumulator Melastoma malabathricum. Compared to seedlings grown in a control nutrient solution containing no Al, mean rates of photosynthesis and respiration increased by 46% and 27%, respectively, total non-structural carbohydrate concentrations increased by 45%, and lignin concentration in roots decreased by 26% when seedlings were grown in a nutrient solution containing 2.0 mM Al. The concentrations of P, Ca and Mg in leaves and stems increased by 31%, 22%, and 26%, respectively, in response to an increase in nutrient solution Al concentration from 0 to 2.0 mM. Elemental concentrations in roots increased for P (114%), Mg (61%) and K (5%) in response to this increase in Al concentration in the nutrient solution. Plants derived from an inherently faster-growing population had a greater relative increase in final dry mass, net photosynthetic and respiration rates and total non-structural carbohydrate concentrations in response to higher external Al supply. We conclude that growth stimulation by Al supply is associated with increases in photosynthetic and respiration rates and enhanced production of non-structural carbohydrates that are differentially allocated to roots, as well as stimulation of nutrient uptake. These responses suggest that internal carbon assimilation is up-regulated to provide the necessary resources of non-structural carbohydrates for uptake, transport and storage of Al in Melastoma malabathricum. This physiological mechanism has only been recorded previously in one other plant species, Camellia sinensis, which last shared a common ancestor with M. malabathricum more than 120 million years ago.

A novel reconstruction technique for chronic lateral ankle instability: comparison to primary repair

Twenty patients with lateral ankle instability were treated by a novel anatomical reconstruction technique (group A) and the results compared with 20 patients (group B) who, during the same period of time, underwent primary repair of ruptured lateral ligaments of the ankle. We reviewed 15 patients from group A and 17 patients from group B at a mean follow-up of between 2 and 4 years. The mean functional scores were good in both groups without significant difference, and there was no difference in the mean anterior talar translation between the two groups. We therefore conclude that chronic lateral instability of the ankle may be successfully treated, even in the presence of severely damaged, attenuated or absent ligament tissue.

Spatial and temporal variability of blood flow in stimulated dog gastrocnemius muscle

The distribution of blood flow in skeletal muscle stimulated to rhythmic isotonic contractions was studied by injections of radioactive microspheres into the arterial supply of gastrocnemius muscles (mean weight 88 g) subsequently cut into 0.5 g pieces for determination of radioactivity. The coefficient of variation (CV = SD/mean) of the ratio of simultaneously injected 10 microns and 15 microns microspheres, 0.12, was taken as the inherent scatter of the method. The average spatial distribution inequality of 10-15 microns microspheres corresponded to a CV of 0.45 and the specific local blood flow inhomogeneity to a CV = 0.43 (= square root of 0.45(2) - 0.12(2)), but there were marked differences between muscles. The temporal variability of blood flow in individual muscle pieces was obtained from the comparison of fractional trapping of 4 to 5 differently labeled microspheres injected at intervals of 2 minutes into steadily stimulated muscles. The mean CV for the variations in time was 0.23 and that corrected for methodological scatter, 0.19. There were large differences between muscle pieces within a muscle and between muscles. The presence of considerable spatial and temporal variations of blood flow in exercising muscle during apparent steady state may be important in limiting and/or modulating tissue O2 supply.

Blood flow distribution and its temporal variability in stimulated dog gastrocnemius muscle

The distribution of blood flow in skeletal muscle stimulated to rhythmic isotonic contractions was studied by injections of radioactive microspheres into the arterial supply in 8 gastrocnemius muscles (mean weight 84 g) of 6 anesthetized dogs (20-25 kg body weight). The distribution of 10 micron microspheres in regions of about 0.5 g was very similar to that of the standard 15 micron microspheres, whereas that of 25 micron microspheres was more uneven. The coefficient of variation (CV = SD/mean) of the ratio of simultaneously injected 10 micron and 15 micron microspheres, 0.12, was taken as the inherent scatter of the method. The average spatial distribution inequality of 10-15 micron microspheres corresponded to a CV of 0.45 and the specific local blood flow inhomogeneity to a CV = 0.43 ( = square root 0.45(2) - 0.12(2], but there were marked differences between muscles. At equal blood flow levels, the inhomogeneity during reactive hyperemia was similar to that observed during stimulation. The temporal variability of blood flow in individual muscle pieces was obtained from the comparison of fractional trapping of 4 to 5 differently labeled microspheres injected at intervals of 2 min into steadily stimulated muscles. The mean CV for the variations in time was 0.23 and that corrected for methodological scatter, 0.19, but the differences in the extent of temporal blood flow changes among muscle pieces within a muscle and between different muscles were large. The presence of considerable spatial and temporal variations of blood flow in exercising muscle during apparent steady state may be important in limiting and/or modulating tissue O2 supply.

Cardiac dysrhythmias associated with ophthalmic atropine

Atropine sulfate, a mydriatic and cycloplegic agent, is frequently used in patients undergoing glaucoma surgery. Trabeculectomy with peripheral iridectomy is the most common glaucoma surgery performed to decrease intraocular pressure and preserve vision. Systemic absorption of ophthalmic atropine does occur and may result in toxic and adverse side effects. Cardiac dysrhythmias are one of the major adverse reactions. This case study reviews three patients who had a trabeculectomy for glaucoma and received ophthalmic atropine. One patient received both systemic and ocular atropine. Two patients developed atrial fibrillation and one a supraventricular tachycardia. Two patients required admission to a cardiac intensive care unit for management of the dysrhythmia and a third reverted to normal sinus rhythm spontaneously. The cardiac effects of ophthalmic atropine should be considered in the preoperative and postoperative assessment of patients with dysrhythmias.

The effect of cholecystectomy on the induction of colorectal tumors in mice by 1,2-dimethylhydrazine

The influence of previous cholecystectomy (CCE) on the 1,2-dimethylhydrazine (DMH)-induced colorectal tumorigenesis was examined in 497 female NMRI mice after 14, 20, 24, 28, 33, and 36 weeks of induction time. There were only minor differences between the cholecystectomized and the non-cholecystectomized animals with regard to the percentage of tumor-bearing animals, number of adenomas, and location of the tumors. Only after an induction time of 20 weeks, the operated group had significantly more carcinoma-bearing animals than the non-operated group (P less than 0.01, chi 2-test). The implication of these results on known data of epidemiologic studies in human colorectal cancer are discussed.

Radiographic instability of the ankle joint after Evans' repair

Forty-two unstable ankle joints were treated surgically by Evans' operation. The clinical postoperative results were correlated with the objective radiological stress examinations. The mean age of the patients was 29 years (15-60 years). The clinical and radiological follow-up examinations were performed 6 months after the operation. In the stress X-ray examinations a modified stress frame was used. Clinical instability was noted in four patients. In the radiological examination one patient had a pathological finding in the talar tilt test and 18 patients in the anterior drawer sign test. The radiological instability correlated poorly with the subjective end results. Six patients were estimated to have a poor result of the operation. Five of these patients had a positive anterior drawer sign in the stress X-ray examination and one had degenerative changes in the ankle. Although Evans' repair is a simple and reliable method of reconstructing ruptures of the lateral ligaments of the ankle joint, it is associated with a relatively high frequency of positive anterior subluxation on radiological stress examination. This finding can be explained by the anatomical and geometrical factors on the lateral side of the ankle joint.

[Cholecystectomy, cholelithiasis and cancer of the large intestine]

In a retrospective post-mortem study the connection between the post-cholecystectomy state, cholelithiasis and carcinoma of the large intestine was evaluated in 333 cases and compared with an age and sex matched control group and a group with gastric carcinoma. It was established that cholelithiasis (without cholecystectomy or contracted gallbladder) occurred significantly more frequently (24.9%) in patients with colonic carcinoma than in the control group (15.3%) or the gastric carcinoma group (12.6%) (P less than 0.001). In contrast the rate of cholecystectomy in patients with colonic carcinoma was not significantly increased (6.3%) when compared with both control groups (4.6 and 4.8%). Separate assessment of males and females showed that females had cholecystectomy and contracted gallbladder significantly more frequently (P less than 0.05). These figures suggest that the clinically observed association between cholecystectomy and colonic carcinoma reflects only a - not necessarily causative - connection between gallstone disease and colonic carcinoma.

Cutaneous immunoblastic T-cell lymphoma

The case of a 69-year-old male patient with an unusual type of malignant lymphoma is presented. Clinically, it was at first characterized by follicular papules and erythematous patches, later, by the development of cutaneous tumors and enlarged lymph nodes, and by a severe, finally excruciating pruritus. Treatment with PUVA (psoralen-ultraviolet-A) combined with 40--80 mg prednisolone and then with chemotherapy [COPP regimen (cyclophosphamide, vincristine, procarbacine, prednisone), high-dosage methotrexate followed by citrovorum factor rescue] was not successful. The patient died of pneumonia 2.5 years after the onset of the first clinical symptoms. An immunoblastic infiltrate was observed histologically and electromicroscopically in the initial lesions of the skin. Therefore, the diagnosis of a cutaneous immunoblastic T-cell lymphoma was tentatively made at the beginning, which was later confirmed in numerous biopsies and laboratory investigations. Immunocytologically and enzymecytochemically, the infiltrating cells were shown to be immature T cells; in the lymph nodes, numerous immunoblasts and large Sézary cells was observed in the peripheral blood, though there were no very large Sézary cells or blast cells. In the autopsy, a systemic involvement with an atypical lymphoid infiltration was found in numerous internal organs. The special nature of this case justifies its classification as high-grade malignant lymphoma and its differentiation from normal cases of mycosis fungoides. In contrast, mycosis fungoides generally fulfils criteria typical of low-grade malignant lymphomas.

[Malignant hyperthermia. A case report (author's transl)]

An exceptionally serious case of malignant hyperthermia in a 17 year old male is presented. A detailed description of the case is given concerning symptomatology, course, laboratory data and morphologic alterations. Our patient died after 7 weeks of intensive care due to therapy resistant septicemia and coagulation disorder. Intense adynamia and advanced muscular atrophy were present. Necropsy showed regionally different extensive lysis of skeletal muscles. In the discussion the advantage of an "ice gravel" producing machine in cooling measures, the necessity of higher procaine doses and problems of long term therapy in trauma patients coincidentally affected with malignant hyperthermia, are stressed.

[Osteochondritis dissecans of the patella (author's transl)]

Five cases of osteochondritis dissecans patellae were seen and followed during years 1971--1978. Special interest was pointed to the site of the lesion, at which age the disease appeared, and to the physical activity of the patients. In one case only patellar subluxation could be confirmed. In two cases radioisotope (Tc99) szintigraphy was done with positive finding. The radiological finding was typical in all cases. The treatment was conservative in all cases but one. Loose body formed once in the series. Operative treatment should be directed only to the cases with persistent symptoms and/or loose bodies.

Hypercapnia and resultant bicarbonate transfer processes in an elasmobranch fish (Scyliorhinus stellaris)

In order to test the effects of hypercapnia on the acid-base status of fish, larger spotted dogfish were exposed to sudden changes of PCO2 in a closed seawater recirculation system. pH, PCO2 and PO2 were determined in arterial blood and seawater. The exchange of bicarbonate between extracellular space (ECS), intracellular space (ICS), and seawater (SW) was obtained from changes of the total bicarbonate amount in ECS and SW. After fourfold increase of PCO2 arterial pH fell markedly, but started to recover immediately towards control values. This was caused by compensatory accumulation of bicarbonate in the ECS. According to the origin of the extracellular bicarbonate increase three periods could be distinguished: 1.-- Bicarbonate transferred from ICS to both ECS and SW; 2. -- Bicarbonate transferred from both SW and ICS to ECS; 3. -- Bicarbonate transferred from SW to both ECS and ICS. After return to normocapnia similar periods occurred with opposite transfer directions and delayed period transitions. In the first period the ICS was found to be the only source for compensatory bicarbonate increases and even in the second period the ICS contributed to compensation of the extracellular pH. Thus bicarbonate exchange with the ICS appears to be an important regulatory mechanism diminishing the extracellular pH variations after changes in PCO2, before other compensatory mechanisms are initiated.