PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “TROPICAL CLIMATE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMed1993

Higher incidence of catheter-related infections in a tropical climate.

Catheter-related infections (CRIs) have become a prominent morbidity factor in continuous ambulatory peritoneal dialysis (CAPD). To confirm a clinical impression that CRI rates in our population (n = 80, 1080 patient-months) were unusually high, a retrospective study was performed. In addition, data from adult patients treated for at least 12 months were analyzed (n = 28, 325 patient-months) to determine if climate conditions could account for our findings. Comparisons were made between CRI rates during months with a mean maximal temperature of 32 degrees C or higher (hot season) and CRI rates during months with a mean temperature lower than 28 degrees C (control season). Two-cuff Tenckhoff catheters were used on 68 occasions and the Swan neck Missouri catheter 2 on 20 occasions. Main CAPD systems were the O-set (n = 48) and the disposable Y-set (n = 35). A total of 139 CRI episodes were recorded with a rate of 1/8 patient-months. A CRI was implicated as a causative factor in 18 of 69 episodes of peritonitis (26%) and in 13 of 27 catheter losses (48%). CRI rates were similar when comparing either Swan neck versus Tenckhoff catheters (1/7 and 1/8 patient-months) or the O-set versus disposable Y-set (1/7 and 1/10 patient-months). Most importantly, a significantly higher incidence of CRI was found during the hot seasons in comparison to the control seasons (1/9 vs 1/19 patient-months, p < 0.05, one-way signed rank test). Our data suggest that a hot climate can adversely affect the rate of CRIs.

Brazil↗
PubMed1984

[Tenacity of bacteria in the airborne state. III. Model studies on the epidemiology of Pasteurella multocida influenced by a tropical climate].

The viability of airborne P. multocida in a static aerosol chamber was determined at temperatures of 21, 24, 28, 34, 40 and 42 degrees C and relative humidities of 44, 70 and 87%. The greatest viability with 35.49 min half-life time was at 24 degrees C and 70% relative humidity. There was no separate influence of one of the climatic components temperature and relative humidity to the airborne viability of the germs. The lowest resistance of P. multocida in the airborne state was as they were solitary germs, but as agglomerates (1.5-3.5 micron) they survived also worse environmental conditions.

Air Microbiology↗
PubMed2006

Malaria rapid diagnostic tests in tropical climates: the need for a cool chain.

Malaria control programs in endemic countries increasingly rely on early case detection and treatment at village level. The rapid diagnostic tests (RDTs) and accompanying drugs on which the success of these programs depends deteriorate to varying degrees at high temperatures. To assess the ability of health systems to maintain RDTs within manufacturers' specifications, we monitored temperatures in the delivery chain from manufacturer through to the village health worker in Cambodia and the Philippines. In both countries, storage temperatures regularly exceeded those recommended for most RDTs intended for field use, whereas temperatures during transport greatly exceeded the lower and upper limits. These results emphasize the need for good logistical planning during the introduction of point-of-care tests in tropical countries and the importance of considering the stability of diagnostic tests during procurement.

Cambodia↗
PubMed1975

Water balance and body weight: studies in a tropical climate.

Total body weight, water balance and energy balance were estimated in young adult men in a hot climate, over three 6-day periods. The aim was to determine the relative contributions to body weight changes of fluctuations in water and energy stores. In these subjects, the small observed body weight changes were due almost entirely to water balance changes. Water balance was regulated to within +/- 1% of body weight from day-to-day.

Adult↗
PubMed2005

Landfill leachate treatment by an experimental subsurface flow constructed wetland in tropical climate countries.

Municipal leachate was treated in an experimental unit of constructed wetlands of subsurface flow type. The parameters studied were organics (BOD and COD), solids and heavy metals (Zn, Ni, Cu, Cr and Pb). Using two types of emergent plants of Scirpus globulosus and Eriocaulon sexangulare, more than 80% removal was achieved for all the parameters. E. sexangulare removed organics and heavy metals better than Scirpus globulosus. A higher concentration of heavy metals in the influent did not change the removal efficiency.

Cyperaceae↗
PubMed2005

Association of air-conditioning with respiratory symptoms in office workers in tropical climate.

UNLABELLED: To evaluate the association of heating, ventilation and air-conditioning systems (HVAC) and respiratory symptoms in a tropical city, self-administered questionnaires were given to 2000 individuals working in air-conditioned office buildings and to 500 control workers in naturally ventilated buildings. Reported symptoms from the two populations were analyzed using chi-square tests, univariate and multiple logistic regressions models. Symptoms were the outcome variable and the odds ratios were adjusted by gender, age, accumulated work time, smoking habits and atopic background. There was a 79.8% response rate and there was a positive association of nasal symptoms (odds ratio, OR = 1.59, 95% confidence interval, CI = 1.11-2.28), naso-ocular symptoms (OR = 1.58, 95% CI = 1.05-2.38), persistent cough (OR = 3.04, 95% CI = 2.00-4.63) sinusitis symptoms (OR = 1.85, 95% CI = 1.27-2.71) and building-related worsening of the symptoms (OR = 4.92, 95% CI = 2.93-8.27) with working in air-conditioned buildings. In conclusion, our study suggests that artificial air-conditioning is a matter of concern for respiratory symptoms in cities with hot and humid climate. PRACTICAL IMPLICATIONS: This study suggests that indoor air-related respiratory symptoms are a matter of concern in places with hot and humid climate. The regression models were adjusted by confounders that could be used in further reanalysis of indoor air quality related symptoms and ventilation systems with expanded variety of climatic conditions.

Adult↗
PubMed2002

Removal of iron and manganese by artificial destratification in a tropical climate (Upper Layang Reservoir, Malaysia).

Environmental monitoring was carried out at Upper Layang Reservoir situated in Masai, Johor, Malaysia. The study shows that thermal stratification and natural mixing of the water column do exist in the reservoir and the level of stratification varies at different times of the year. Artificial destratification via diffused air aeration techniques was employed at the reservoir for two months. The results show that thermal stratification was eliminated after a week of continuous aeration. The concentrations of iron and to a lesser extent manganese in the water column was also reduced during the aeration period.

Iron↗
PubMed1987

[Drinking water problems in tropical climates as in the example of Abeokuta, Nigeria].

In June 1986, bacteriological and chemical examinations of drinking-water were carried out in Abeokuta (Ogun State, Nigeria) and in surrounding areas. The analysis showed that the population of this region is not provided with drinking-water of suitable quality, as defined by international standards. In could also be established that secondary contamination, due to inappropriate transport and storage of the water, leads to further reduction in the quality of the already contaminated water. These results show that this contaminated drinking-water must be considered as the major cause of numerous intestinal infections.

Animals↗
PubMed1991

[Characteristics of tuberculosis of the respiratory organs in patients living in the areas of tropical climate].

Factors that underlie the generally acknowledged high-risk groups are supplemented by specific aggravating factors typical of hot-climate regions: recent (less than 5 years) staying in hot regions, frequent childbirth in the indigenous women and overheating under industrial and living conditions. Subjects having a combination of several aggravating factors have the most serious tuberculosis structure. The preventive measures should aim at recording of such subjects and making obligatory X-ray and fluorographic examination accomplished every year and controlled by the antituberculosis dispensaries. A combination of several unfavourable factors requires employment of general health measures; in immunity lowering threat chemoprophylaxis should be prescribed.

Adult↗
PubMed2003

[Management of severe malnutrition in children in tropical climates].

Severe malnutrition is defined as a weight for height index less than-3 standard deviations (SD) from the NCHS reference or the presence of edema. Without appropriate treatment, the risk of death is high. The WHO now proposes a standardized treatment protocol that consists of first treating initial complications and then two-phased feeding with two therapeutic formulas (milk F75 and milk F100) made of dried skimmed milk, oil and sugar highly supplemented with vitamins and minerals but containing no iron. Milk F75 featuring moderate protein and energy content is used for the first few days until associated infections are under control and anorexia disappears. Milk F100 featuring higher energy and protein content that allows high weight gain is subsequently used for nutritional rehabilitation. Milk F100 is gradually replaced by solid diets for home based nutritional rehabilitation.

Animals↗
PubMed2003

Performance of a small wastewater stabilisation pond system in tropical climate in Dar es Salaam, Tanzania.

Waste stabilisation ponds (WSP) are widely used in Tanzania. Their traditional design focuses on BOD and pathogen removal, but nutrient removal is equally important. WSP performance was evaluated to come up with information that would be used to evaluate pond performance. Samples were analysed twice a month for six months. Results showed total and faecal coliform removal by 4 log units (99.96 and 99.98% respectively). There was partial reduction of COD, BOD, (46% and 27% respectively), conductivity and total dissolved solids (32.6 and 32.4% respectively). Variation for the nutrients like inorganic phosphorus, ammonia nitrogen, nitrite nitrogen, and nitrate nitrogen was not consistent and there was practically no reduction, although there is some nitrification taking place. From this study it may be concluded that BOD and nutrients may not be useful to evaluate pond performance. Instead parameters such as conductivity, total dissolved solids, coliform bacteria, dissolved oxygen, pH and chlorophyll would be suitable for that purpose, due to their consistent variation within cells of the pond system. But BOD and nutrient removal are important and have to be improved to enhance treatment in the WSP.

Chlorophyll↗
PubMed1979

Seasonal effects of tropical climate on shaded and nonshaded cows as measured by rectal temperature, adrenal cortex hormones, thyroid hormone, and milk production.

Rectal temperatures and hormone concentrations were monitored at intervals of 2 to 3 weeks, and milk, milk fat, and California mastitis test scores at intervals of 1 week in five shaded and in four nonshaded early lactation cows. Measurements were taken from September to December in the mildly heat stressing climate of Oahu, Hawaii. The daily ambient temperature flux ranged from 22 C to 29 C in September to 20 C to 25 C in December. Average daily temperature-humidity index (THI) values were 75 to 70 for September and December, respectively. Average daily THI values were correlated with rectal temperatures in nonshaded cows and were negatively correlated with plasma adrenal cortex hormones (corticoids) in shaded cows, plasma thyroid hormone in shaded and nonshaded cows, and with milk production in nonshaded cows. Estimated milk production decline per unit increase in THI was 0.32 kg. Nonshaded cows had higher rectal temperatures, a trend for lower plasma corticoids, produced less milk and milk fat, and had higher California mastitis test scores. Shaded cows maintained a higher fat percentage at THI above 74. Average plasma thyroid hormone values were not different between treatment groups. Both groups failed to attain normal rectal temperatures at night. Afternoon rectal temperatures were more highly correlated with the rectal temperature with which the cow started the day than they were with the THI of the day itself.

Adrenal Cortex Hormones↗
PubMed1998

Self-selection of dietary protein and energy by broilers grown under a tropical climate: adaptation when exposed to choice feeding at different ages.

Three hundred broiler chicks (Hubbard) of both sexes were assigned to five feeding treatments: T0 received a complete diet (control), T1 was a choice feeding system with simultaneous access to an energy-rich feed (ground corn) and a protein concentrate (43.7% CP), and T2, T3, and T4 were introduced to choice feeding after 1, 3, and 5 wk, respectively, of consuming the complete diet. At 1-d-old, T1 chicks showed a marked preference for corn, with only 21.4% of their intake being the protein concentrate diet. Intake of the concentrate progressively increased to 40 to 45% after 3 d of adaptation, resulting in diets with 22.5 to 24.3% CP. When broilers fed the complete diet for 1 to 5 wk (T2, T3, T4) were changed to choice feeding, on the 1st d, their feed choice intake was similar to that of T1 chicks at the same age. Visual observation and tactile assessment of the feed particles during the initial period allowed the chicks to quickly evaluate the new feeds and to adapt their feeding behavior. Although total feed intake to 6 wk of age was not significantly affected by the feeding treatments, broilers on choice feeding selected diets with a lower percentage of CP and had lower live body weights at 6 wk than those fed the complete diet (T0).

Adaptation, Physiological↗
PubMed1997

Self-selection of dietary protein and energy by broilers grown under a tropical climate: effect of feed particle size on the feed choice.

Broilers, 2 wk of age, that had been previously adapted to energy: protein choice feeding, were offered corn (either ground, cracked, or presented as whole grains) and a protein concentrate (43.7% CP) in mash or pellet form. When corn was fed as whole grains, protein concentrate in the selected diet was significantly higher (35.1%) than with cracked corn (29.3%) or ground corn (29.1%). Presenting the concentrate as pellets resulted in a significantly higher concentration in the diet (32.7%) than when mash concentrate was fed (29.6%). Live BW at 4 and 6 wk of age were not significantly affected by feed texture. However, offering corn as whole grains or concentrate as pellets induced a significant improvement in feed efficiency. Total time to eat larger size particles (whole grains, pelleted concentrate) was significantly less than total time to eat ground corn or mash concentrate. Furthermore, the mean duration of the feeding bouts was two times shorter for whole grains (48 s) than for ground corn (98 s) and for pelleted concentrate (56 s) than for mash concentrate (114 s). Chickens ate whole grains or pellets at a significantly slower rate (number of pecks per second feeding time) than when eating ground corn or mash concentrate. There was a rejection during the first 24 h when the form of the concentrate (mash to pellets) was changed. Full adaptation to the new size of the concentrate required about 3 d.

Analysis of Variance↗
PubMed1999

Hematocrit and stroke in black Africans under tropical climate and meteorological influence.

OBJECTIVES: To assess the relationship between hematocrit and risk of fatal and non-fatal stroke in conjunction with meteorological variations. DESIGN: Prospective study of a series of Africans living in Kinshasa, Congo, followed up for 5 years. SUBJECTS: A total of 1,032 unselected patients consecutively admitted to hospitals for acute stroke. Main outcome measures. Fatal and non-fatal ischemic or hemorrhagic strokes. The association of hematocrit with stroke morbidity and mortality and meteorological variables were evaluated by simple or multiple linear regression and logistic regression. RESULTS: Patients were aged 53.7 +/- 12.1 years. Hematocrit was mostly correlated with mean ambient air temperature (r = 0.124; p < 0.001) and atmospheric pressure at 6 a.m GMT (r = 0.157; p < 0.001). Patients with hematocrit > 40% presented the highest levels of systolic blood pressure, fibrinogen, body temperature, resting heart rate, duration of coma and incidence of all stroke types and ischemic stroke (p < 0.001). Hematocrit > 40% was associated with stroke mortality (Odds ratio, 6.2, 4.5-8.6; p < 0.001). The risk of stroke mortality was multiplied by 21, 18.3 and 4.2 in conditions of a mean ambient air temperature > 28 degrees C, atmospheric pressure 975-977 mm Hg and body temperature > 37 degrees C respectively. CONCLUSIONS: Our study suggests that higher hematocrit is associated with an increased risk of stroke morbidity and mortality, particularly ischemic stroke at noon. This risk is probably mediated by increased susceptibility of African older hypertensive subjects to meteorological variations.

Adolescent↗
PubMed1993

[Ectopic pregnancy in tropical climate. An ultrasonographic study of 93 consecutive cases].

BACKGROUND AND PURPOSE: Ectopic pregnancy (EP) is common in Cameroon, and incidence is increasing. Ultrasound (US), has been shown to play a key role in its diagnosis, particularly when the transvaginal (TV) route is used. The purpose of our work is to describe sonographic features of EP, and to assess the role of the transvaginal route in the diagnosis of this disease in our environment. PATIENTS AND METHODS: The study was prospectively carried in the US unit of the Yaoundé University teaching Hospital (Cameroon) during a 2 year period. 502 patients aged 14 to 45 were included because of clinical suspicion of EP. The criteria for sonographic diagnosis of EP were the presence of an embryo outside the uterus, a ring-like adnexal structure, or complex adnexal mass separate from the ovaries, in conjunction with free peritoneal fluid. The EP was considered ruptured if significant fluid was found in the upper peritoneal recesses. The diagnosis was confirmed by laparoscopy or laparotomy. RESULTS: Ninety six patients were found to have an EP. 56 patients had only TV pelvic US, 13 had both TV and TA routes, and 24 patients had only TA pelvic US. The mean age was 29 years (interval: 17-42). The main clinical findings included: pain (88%), amenorhea (84%), bleeding (72%), cardio-vascular instability (14%), pelvic mass (9%). The pregnancy was tubal for 93 patients, and abdominal for 3. It was ruptured for 46 (49%). Adnexal abnormalities were present for 86 patients (92%). These were a gestational sac (78%) with a living embryo in 31 patients (33%), or a complex adnexal mass (15%). Uterine findings (40%) included: endometrial thickening (20%), pseudosac (19%), fibroids (6%). An ovarian cysts was present for 10 patients. As a rule, TV route delineated all these findings better than the TA route. CONCLUSION: An exceptionally high proportion of EP was seen after rupture in this study. Our recommendations include: educate patients to seek immediate medical advice for any missed period associated with pain, increase health providers' awareness of EP, and promote availability of TVUS.

Adolescent↗
PubMed2006

The road from Santa Rosalia: a faster tempo of evolution in tropical climates.

Using an appropriately designed and replicated study of a latitudinal influence on rates of evolution, we test the prediction by K. Rohde [(1992) Oikos 65, 514-527] that the tempo of molecular evolution in the tropics is greater than at higher latitudes. Consistent with this prediction we found tropical plant species had more than twice the rate of molecular evolution as closely related temperate congeners. Rohde's climate-speciation hypothesis constitutes one explanation for the cause of that relationship. This hypothesis suggests that mutagenesis occurs more frequently as productivity and metabolic rates increase toward the equator. More rapid mutagenesis was then proposed as the mechanism that increases evolutionary tempo and rates of speciation. A second possible explanation is that faster rates of molecular evolution result from higher tropical speciation rates [e.g., Bromham, L. & Cardillo, M. (2003) J. Evol. Biol. 16, 200-207]. However, we found the relationship continued to hold for genera with the same number of, or more, species in temperate latitudes. This finding suggests that greater rates of speciation in the tropics do not cause higher rates of molecular evolution. A third explanation is that more rapid genetic drift might have occurred in smaller tropical species populations [Stevens, G. C. (1989) Am. Nat. 133, 240-256]. However, we targeted common species to limit the influence of genetic drift, and many of the tropical species we used, despite occurring in abundant populations, had much higher rates of molecular evolution. Nonetheless, this issue is not completely resolved by that precaution and requires further examination.

Animals↗