Phenotypic characterisation of Saccharomyces spp. for tolerance to 1-butanol

Biofuels are expected to play a role in replacing crude oil as a liquid transportation fuel, and research into butanol has highlighted the importance of this alcohol as a fuel. Butanol has a higher energy density than ethanol, butanol-gasoline blends do not separate in the presence of water, and butanol is miscible with gasoline (Szulczyk, Int J Energy Environ 1(1):2876-2895, 40). Saccharomyces cerevisiae has been used as a fermentative organism in the biofuel industry producing ethanol from glucose derived from starchy plant material; however, it typically cannot tolerate butanol concentrations greater than 2 % (Luong, Biotechnol Bioeng 29 (2):242-248, 27). 90 Saccharomyces spp. strains were screened for tolerance to 1-butanol via a phenotypic microarray assay and we observed significant variation in response with the most tolerant strains (S. cerevisiae DBVPG1788, S. cerevisiae DBVPG6044 and S. cerevisiae YPS128) exhibiting tolerance to 4 % 1-butanol compared with S. uvarum and S. castelli strains, which were sensitive to 3 % 1-butanol. Response to butanol was confirmed using traditional yeast methodologies such as growth; it was observed that fermentations in the presence of butanol, when using strains with a tolerant background, were significantly faster. Assessing for genetic rationale for tolerance, it was observed that 1-butanol-tolerant strains, when compared with 1-butanol-sensitive strains, had an up-regulation of RPN4, a transcription factor which regulates proteasome genes. Analysing for the importance of RPN4, we observed that a Δrpn4 strain displayed a reduced rate of fermentation in the presence of 1-butanol when compared with the BY4741 background strain. This data will aid the development of breeding programmes to produce better strains for future bio-butanol production.

Integrated waste management for rural development in Egypt

Rural areas generate a large amount of plant and animal residues that can be recycled and utilized instead of relocation and/or burning. This will lead to increasing the benefits from agricultural sector in rural communities and ensuring a better environment. To increase the economic output and environmental benefits of recycling agricultural residues, integrated system should be considered, e.g., energy--compost-recycled water system; composting--co-composting system; food-feed compost system, ensilage of crop residues. The present work was a pilot study for optimizing integrated systems for bioconversion agricultural residues completed by establishing a Training Center for Recycling Agricultural Residues (TCRAR) thereby ensuring the dissemination of the technical, environmental, and socioeconomic aspects to farmers, live stock producers, extensions service staff, and private sector. Three integrated subsystems for bioconversion of agricultural residues were developed. They were based on (i) energy--manure-recycled water system, (ii) composting and co-composting system, and (iii) food-feed/compost system.

Virologic and serologic surveillance for dengue fever in Jeddah, Saudi Arabia, 1994-1999

Dengue fever infection was first documented in Jeddah, Saudi Arabia, by virus isolation of dengue type 2 virus in 1994 at the virology laboratory of Dr. Soliman Fakeeh Hospital. Dengue virus surveillance was established after that time. Blood samples were collected from 985 patients (710 male patients and 275 female patients) with suspected cases of dengue from February 1994 to December 1999. Dengue virus isolates were obtained in 207 patients (21%; 162 male patients and 45 female patients). Dengue type 2 was the predominant serotype (138 of 207 isolates, 66.7%), followed by dengue type 1 with (56 of 207 isolates, 27%) and dengue type 3 (13 of 207 isolates, 6.3%). The largest number of isolates (186 of 207 isolates, 90%) was in 1994, a year during which there was a dengue epidemic. In the next 5 years, 1995-1999, only 21 isolates (10%) were isolated. Immunoglobulin M capture enzyme-linked immunosorbent assay was positive in 160 acute samples; 52 of them were from virus culture-positive cases and 108 (11%) from culture-negative cases. The total number of cases diagnosed by both methods was 315 (32%). The prevalence of dengue immunoglobulin G antibodies, as assessed on the basis of immunofluorescent assay, hemagglutination inhibition titers > or = 1/20, or both, in the acute samples was 314 (32%) of 985, indicating past Flavivirus infection. Two patients died, one man with dengue hemorrhagic fever and one woman with dengue shock syndrome. Both fatal dengue cases were due to infection with type 2 virus. All other cases were simple dengue fever. To our knowledge, this is the first report confirming the circulation of 3 dengue serotypes in Jeddah.

Complete coding sequence of the Alkhurma virus, a tick-borne flavivirus causing severe hemorrhagic fever in humans in Saudi Arabia

To date, tick-borne flaviviruses responsible for hemorrhagic fever in humans have been isolated in Siberia (Omsk hemorrhagic fever virus), India (Kyasanur Forest disease virus, KFDV), and in Saudi Arabia (Alkhurma virus, ALKV). Prior to this study, only partial coding sequences of these severe pathogens had been determined. We report here the complete coding sequence of ALK virus, which was determined to be 10,248 nucleotides (nt) long, and to encode a single 3,416 amino acid polyprotein. Independent analyses of the complete polyprotein and the envelope protein provided genetic and phylogenetic evidence that ALKV belongs to the tick-borne flavivirus group, within which it is most closely related to KFDV. Analysis of structural genes, genetic distances, and evolutionary relationship indicate that ALKV and KFDV derived from a common phylogenetic ancestor and constitute two genetic subtypes of the same virus species according to current genetic criteria of classification.

Hepatitis C: prevalence and common genotypes among ethnic groups in Jeddah, Saudi Arabia

The presence of antibodies to hepatitis C virus (HCV) was examined using a third-generation ELISA in 3,350 serum samples obtained from patients visiting different outpatient clinics, preoperative patients, and women visiting for ante-natal care at the Dr. Fakeeh hospital in Jeddah, Saudi Arabia from January to September 1998. The population included mainly Saudis, Egyptians, and Yemenis, and patients from other Middle East and Asian countries. The prevalence of HCV infection was 5.87% among Saudis, 22.54% among Egyptians, and 2.12% among Yemenis. The prevalence among patients from other Middle East and Asian countries were 3.38% and 4.98%, respectively. The overall prevalence among the studied group was 6.75%. Genotyping of isolates from Saudi Arabia showed that the prevalences of types 4, la, 1b, and 2 were 45.9%, 40.6%, 10.85%, and 2.7%, respectively. Genotyping of isolates from Egypt showed that type 4 was the major type among Egyptians (91.6%), while types 1a and 1b each had prevalences of 4.2%.

Isolation of a flavivirus related to the tick-borne encephalitis complex from human cases in Saudi Arabia

A flavivirus related to the tick-borne encephalitis complex was isolated from the blood of 6 male butchers, aged 24-39 years, in Jeddah, Saudi Arabia in November and December 1995. Two of the patients died and the other 4 recovered completely. Four more patients, 3 males and 1 female, were diagnosed serologically by immunoglobulin M capture enzyme-linked immunosorbent assay and seroconversion in acute and convalescent blood samples examined by indirect immunofluorescent test using Vero cells infected with the isolated virus. The virus identity was confirmed at the Centers for Disease Control and Prevention, Fort Collins, Colorado, USA, by the polymerase chain reaction; it was closely related to Kayasanur Forest disease virus. All infected patients had similar clinical and laboratory symptoms and signs, including fever, headache, generalized body aches, arthralgia, anorexia, vomiting, leucopenia, thrombocytopenia, elevated liver enzymes (serum glutamic oxalacetic and serum glutamic pyruvic transaminases), elevated creatinine phosphokinase, and elevated blood urea. One patient developed symptoms of encephalitis, but survived without any sequel. Skin rash developed in 2 patients, morbilliform on the hands, feet, and lower abdomen of one patient and purpuric associated with melaena in the second patient. Eight of the 10 confirmed patients were working with sheep, and the disease may be a zoonotic viral infection.

Acute appendicitis in children: when does ultrasound help?

Fifty-six patients with possible appendicitis were evaluated clinically and by ultrasound. Ultrasound examination visualized the appendix in 18 of the patients evaluated and showed another pathology in six others. It was useful when the clinical picture was not clear (25 patients) as it showed an inflamed appendix in 10 patients. This was of particular value when there was another critical illness making clinical evaluation difficult (three patients), and for the diagnosis of other unsuspected pathological conditions (six patients). It did not affect the line of management when the clinical picture was clear enough to diagnose or exclude acute appendicitis.

Functional electrical stimulation treatment of postradiculopathy associated muscle weakness

Eighteen chronic pain patients (CPPs) with postradiculopathy-associated muscle weakness were entered into a nonrandomized functional electrical stimulation (FES) clinical treatment study to determine if FES can improve postradiculopathy associated muscle weakness. Because of the clinical nature of the unit, the CPPs could not be denied treatments other than FES. To control for these other treatments, the CPPs were used as their own controls with two control conditions, ie, where possible, the contralateral probable normal muscle was used as a control (control 1) and; in a subgroup of CPPs (n = 6), FES treatment was initially withheld to the probable weak muscle (control 2). Strength was measured as isometric maximum voluntary contraction (IMVC) and was used as the outcome treatment variable. IMVC was measured in both the probable weak and contralateral probable normal muscles at entrance into the Pain Center, at beginning of FES treatment, at completion of FES treatment, and for the control 2 condition at the end of the non-FES treatment period. Statistical analyses of the IMVC strength results using the two control conditions indicated (1) both the FES-treated and untreated muscles increased significantly in IMVC strength, (2) improvement in IMVC strength for FES-treated muscles was significantly greater than for probable normal FES-untreated muscles and, (3) improvement in IMVC strength in FES-treated muscles was significantly greater during the FES-treatment period than during the non-FES treatment period. FES treatment of postradiculopathy-associated muscle weakness in CPPs seems to increase the strength of the probable weak muscle above the increase in strength provided by other concurrent treatments.(ABSTRACT TRUNCATED AT 250 WORDS)

Penile dorsal angulation in a child without epispadias

This is a report on a 5-year-old boy with dorsal penile angulation without epispadias. The surgical correction is described.

Visualization of coronary artery fistula with transesophageal echocardiography

Coronary artery fistulas are relatively uncommon and are usually initially suspected on auscultation of a continuous murmur. Long-term complications include congestive heart failure, endocarditis, ischemia, and atrial arrhythmias. The role of echocardiography in visualization and diagnosis of these fistulas is expanding. We report two cases in which transesophageal echocardiography was used to visualize and better define proximal coronary arteries and coronary artery fistulas.

Effects of vinblastine on calcium distribution pattern and Ca2+,Mg(2+)-adenosine triphosphatase in rat incisor maturation ameloblasts

Vinblastine is known to affect secretory and transport functions of ameloblasts. The effects of vinblastine on distribution patterns of membrane-associated calcium and Ca2+,Mg(2+)-ATPase in maturation ameloblasts were investigated cytochemically. The potassium pyroantimonate (PPA) method was used for localizing calcium and a modified Wachstein-Meisel medium was used to localize Ca2+,Mg(2+)-ATPase. Ultrastructural changes induced by vinblastine included dislocated organelles and reduction or elimination of the ruffled border of the ameloblasts. Membrane-associated calcium pyroantimonate deposits were markedly reduced. The intensity of Ca2+,Mg(2+)-ATPase reaction product was also markedly reduced by vinblastine. Concomitant reduction of membrane-associated calcium and Ca2+,Mg(2+)-ATPase lends support to a role for maturation ameloblasts in control of a cyclic pattern of influx of calcium to mineralizing enamel.

Spontaneous regression of patient omphalomesenteric duct: from a fistula to Meckel's diverticulum

A newborn with a patent omphalomesenteric duct is described in this report. This anomaly is a very rare one. Regression of the omphalomesenteric duct occurs as a normal embryonic event in the intrauterine life between the fifth and ninth week of gestation; however, in this case regression occurred spontaneously in the neonatal period and resulted in a Meckel's diverticulum with no connection with the umbilicus. This is the first case to be reported.

The role of home environment in infant diarrhea in rural Egypt

In 1982 and 1983, a descriptive environmental survey was conducted in 317 households with newborn infants in rural Bilbeis, Egypt. The incidence of infant diarrhea in these households was ascertained by twice-weekly home visits for a 1-year period (1981-1982). Using univariate and multivariate analyses, the authors identified household factors that were statistically associated with infant diarrhea incidence, including number of children in the house under 4 years of age; number of persons per household; incidence of diarrhea in other family members; having a dirt (vs. concrete) dining room floor; having multiple living areas in the house; having a house or roof in need of repair; using well water rather than tap water for cooking or bathin; the absence of a sewer for waste bathwater; food being left out at room temperature between meals; and having many rodents in the house. Two practices involving interaction with the environment appeared to be protective: butchering of cattle by the family for home consumption, and protection of the infant from flies by a veil during napping. The combined household variables explained 25% of the variance in the total incidence of diarrhea. Categories of variables that accounted for most of the total variance explained by environmental factors are, in decreasing order: house structure (28%); water usage (24%); toilet and bathing area (12%); animal management (11%); food preparation area (10%); hygiene (8%); and wastewater management (6%). This approach may be useful in identifying environmental characteristics whose change would reduce diarrheal illness among infants.

Cytochemical localization of calcium and Ca2+,Mg2(+)-adenosine triphosphatase in colchicine-altered rat incisor ameloblasts

Colchicine is known to affect secretory, transport, and degradative functions of ameloblasts. The effects of colchicine on membrane-associated calcium and Ca2+,Mg2(+)-ATPase in secretory and maturation ameloblasts were investigated cytochemically. The pyroantimonate (PPA) method was used for localizing calcium and a modified Wachstein-Meisel medium was used to localize Ca2+,Mg2(+)-ATPase. Sections representing secretory and early maturation stages were examined by transmission electron microscopy. Morphological changes induced by colchicine included dislocated organelles and other well-established reactions to such anti-microtubule drugs. Calcium pyroantimonate (Ca-PA) deposits in most ameloblast types were markedly reduced, with the greater reduction occurring in those cells more severely altered morphologically. However, the cell membranes of both control and experimental smooth-ended maturation ameloblasts were essentially devoid of Ca-PA. The normal distribution and intensity of Ca2+,Mg2(+)-ATPase was not affected by colchicine. Because the observed reduction of membrane-associated calcium is apparently not mediated by Ca2+,Mg2(+)-ATPase in this case, other aspects of the calcium regulating system of ameloblasts are apparently targeted by colchicine.

An observational study of naturally acquired immunity to rotaviral diarrhea in a cohort of 363 Egyptian children. Calculation of risk for second episodes using age-specific person-years of observation

A cohort of 363 rural children in Bilbeis, Egypt, were followed from birth from 1981 to 1983, with twice-weekly home visits made to detect diarrheal illness. Enzyme-linked immunosorbent assay was used for detection of rotavirus in stools collected during episodes of diarrhea. Rotavirus-associated diarrhea was detected once in 74 children and twice in 12 children. Using a technique not previously described, the authors calculated the age-specific incidence rates for initial episodes and second episodes of rotavirus-associated diarrhea to estimate the effectiveness of naturally acquired immunity. Assuming that the risk of exposure was the same before and after the first episode, the observed and expected numbers of second episodes of rotaviral diarrhea were equal (age-adjusted rate ratio = 1.01; 95 percent confidence interval 0.55-1.86), given the age-specific person-years at risk. The assumption of equal risk for reexposure to rotavirus appears to be invalid, however, since the children with one and two rotavirus-positive episodes appeared to be at greater risk for diarrheal illness of all causes (rate ratios of 1.42 and 1.78, respectively). The clinical illness may have been less severe in second episodes; emesis was reported more often with first rotavirus episodes than with second rotavirus episodes, and the only fatal case was in an initial episode. These data are compatible with the existence of partial immunity, since it appears that the risk of reexposure may be greater in children who experienced rotaviral gastroenteritis earlier in life. In four of seven children, rotavirus isolates from first and second episodes were of identical serotypes, indicating that even serotype-specific immunity for rotaviral diarrhea was incomplete.

Illness and reservoirs associated with Giardia lamblia infection in rural Egypt: the case against treatment in developing world environments of high endemicity

A longitudinal investigation of the health effects and reservoirs of Giardia was undertaken during 1984-1985 in 40 households located in the rural Nile Delta region of Egypt. Stool specimens obtained once weekly for six months from 2-4-year-old children were cyst- or trophozoite-positive in 42% of the 724 examined. Only one child remained Giardia-negative during the study. The mean duration of excretion in Giardia-positive children was seven and one-half weeks with a range of one to 17 weeks. Mucus was present in 52% of all stools collected, and fecal leukocytes were observed with surprising frequency in the absence of identifiable pathogens. Clinical symptoms of illness were frequently observed within a month before or after Giardia excretion in stool of children, but a statistical inference of association was not demonstrated. Seventeen per cent of 697 specimens obtained from their mothers were Giardia-positive for a mean duration of four weeks and a range of one to 18 weeks. A total of 962 specimens were collected from 13 species of household livestock. Giardia was detected in 22 specimens from cows, goats, sheep, and one duck. Giardia cysts were detected in three of 899 samples of household drinking water. The ubiquity of the protozoan as well as the failure to show an association between infection and symptomatic illness argue against the administration of Giardia-specific drugs to children in settings where the risk of reinfection is high and for whom intestinal insults are both varied and constant.

Detection of enteropathogens in fatal and potentially fatal diarrhea in Cairo, Egypt

A 1-year study of the etiology of acute diarrhea complicated by severe (10%) dehydration, active bleeding, shock and cardiovascular collapse, pneumonia, acute renal failure, or seizures in infants under 18 months of age was performed in Cairo, Egypt. Of 145 infants, 19 (13%) died or left the hospital moribund; the remaining 126 patients were classified as having potentially fatal illness. A variety of enteropathogens were identified with approximately equal frequency in the fatal and nonfatal complicated cases as well as in 135 controls with severe uncomplicated diarrhea. The agents most frequently detected in infants with severe diarrhea in this population which were felt to be etiologically important were rotavirus (33%), heat-stable enterotoxin-producing Escherichia coli (20%), heat-labile enterotoxin-producing E. coli (11%), enteropathogenic E. coli (8%), and Salmonella spp. (5%). The high rate of occurrence of Giardia lamblia (35%) probably represented the high carriage rate of the protozoan in this population. Complicated (fatal and potentially fatal) cases differed from control cases in a number of ways: the onset of diarrhea was more sudden, the course was progressive and of greater initial intensity, vomiting occurred more frequently, the patients more often had visited another physician before coming to the hospital, the patients more often had respiratory symptoms and pulmonary abnormalities on auscultation, hypoactive bowel sounds and abdominal distention were more common, as was oliguria, and the patients showed lower mean body weights.

The incidence of diarrheal disease in a defined population of rural Egypt

A prospective study of diarrheal illness was conducted for 2 years in 309 families who were part of an epidemiologic research center population in rural Egypt. The rates of illness peaked in the first year of life with between 5 and 6 episodes per person year at risk. Although no seasonal variation in reported diarrhea was demonstrated for the total population, age-specific differences in seasonal occurrence were noted. The incidence did not consistently vary by village size, nor did rates vary by sex.

The detection of enteropathogens in acute diarrhea in a family cohort population in rural Egypt

In 8 villages of rural northeastern Egypt, a 2-year study of the etiologic agents associated with episodes of diarrhea was carried out. Stool specimens (3,243) from 3,513 episodes of diarrhea were processed for enteropathogens. The most commonly identified agents in the group with diarrhea were Giardia lamblia (44%), heat stable enterotoxin (ST)-producing enterotoxigenic Escherichia coli (ETEC) (15%), heat labile toxin (LT)-producing ETEC (12%), enteropathogenic E. coli (EPEC) (4%), rotavirus (3%), Shigella (2%) and Salmonella (1%). Isolation rates were increased in cases compared to controls for all agents except G. lamblia and EPEC strains. Rotavirus, Salmonella and ST-producing ETEC were more frequently isolated during cooler months and Shigella and LT-ETEC occurred more commonly in warmer months. Campylobacter, EPEC, Giardia and E. histolytica did not show a discernable seasonal pattern. Rotavirus was primarily associated with diarrhea in infants only. Forty-four percent of children experienced at least 1 bout of rotavirus diarrhea by the age of 3 years. Vomiting was reported in 65% of cases of rotavirus infection. Dehydration was reported in greater than 40% of those with rotavirus-, Salmonella-, Campylobacter-, LT-ETEC- and EPEC-associated illness and in those without an identifiable agent. While rotavirus was implicated in 3% of cases overall, when vomiting or vomiting plus dehydration occurred, rotavirus was identified with a rate of 10% and 12%, respectively. Dysentery was common only in Shigella cases, occurring in 24%. A decrease in occurrence of rotavirus, Campylobacter and possibly EPEC illness was seen in the infants less than 6 months of age who were breast-fed when compared to those who were not.

Cultivation and subgroup determination of human rotaviruses from Egyptian infants and young children

Primary African green monkey kidney cells were more sensitive than primary cynomolgus monkey kidney and MA104 cells for supporting the growth of human rotaviruses detected in diarrheal stools of Egyptian infants and young children. In attempts to characterize these Egyptian rotaviruses, only 31% of the strains tested in the form of fecal suspensions were identified as subgroup 1 or 2. After one passage in African green monkey kidney cells, 80% of the strains were identified as subgroup 1 or 2. Of these 43 rotaviruses for which the subgroup was determined, 28% were subgroup 1 and 72% were subgroup 2. Thus, cultivation in African green monkey kidney cell cultures facilitated the antigenic characterization of rotaviruses by subgrouping; cultivation also represents an initial step in determining serotype and in developing potential vaccine candidates.

The activity of serum ribonuclease in protein-energy malnutrition

Serum alkaline ribonuclease activity and serum albumin concentration were determined in 25 normal children and 59 children with protein-energy malnutrition. The increase in serum ribonuclease was marked in marasmus and marasmic kwashiorkor. The ribonuclease activity dropped significantly after two weeks of treatment and returned to normal by four weeks. In kwashiorkor, serum ribonuclease activity was significantly lower than control and returned to normal after four weeks of treatment. These findings support previous observations that the serum ribonuclease is a good criterion of the nutritional status and indicates that the enzyme activity, particularly when related to serum albumin, is a good prognostic index in this respect.