Diversity of fungal pathogens in leaf spot disease of Indian mulberry and its management.

Leaf spot disease in mulberry significantly affects silk production by reducing the nutritive quality of the leaves. This disease caused by various pathogens, regardless of the localities under the same climatic region. In the present investigation, an approximate incidence rate of 84 % was recorded in Karnataka based on surveys conducted in both farmer fields and germplasm locations. The causative agents have shown diversification, including new candidates such as Bipolaris sorokiniana, Curvularia lunata, Cladosporium sphaerospermum, and Epicoccum sorghinum. These findings mark the first report of these pathogens in Indian mulberry production. The investigation involved detailed pathogenicity assessments on the predominant mulberry silk production cultivar under controlled and field environments. Pathogens were identified using morpho-cultural, microscopic and phylogenetic analyses, including the internal transcribed spacer (ITS). Various concentrations of fungicides, both individually and in combinations, were evaluated to identify effective measures for mitigating yield losses. Among the fungicides tested against the new pathogens, Hexaconazole 5 % SC and Hexaconazole 5 % + Captan 70 % WP demonstrated high promise and cost-effectiveness. Consequently, these fungicides could serve as immediate solutions to prevent further yield reduction. However, it is essential to conduct comprehensive field investigations before recommending them as standard practices. Future research endeavors should focus on assessing the extent of crop loss caused by these newly identified pathogens in mulberry cultivation.

Genetic Diversity, Identification, and Utilization of Novel Genetic Resources for Resistance to Meloidogyne incognita in Mulberry (Morus spp.).

Mulberry (Morus spp.) is an important crop in the sericulture industry, as the leaves constitute the primary feed for the silkworm. The availability of diverse genetic sources of resistance to root-knot nematode (RKN; Meloidogyne spp.) are very scanty. To address this need, a set of 415 varied exotic and indigenous germplasm accessions were screened under glasshouse conditions. Twenty-one accessions were identified as highly resistant and 48 were resistant, with the highest numbers of highly resistant/resistant accessions being found in Morus alba. Further, 30 accessions based on rooting ability were evaluated for field resistance at four different locations with infested soil. Finally, eight germplasm accessions (BR-8, Karanjtoli-1, Hosur-C8, Nagalur Estate, Tippu, Calabresa, Thai Pecah, and SRDC-3) were identified as potential genetic sources in RKN-resistance breeding programs or as resistant rootstock for the establishment of mulberry gardens. Sixteen simple sequence repeat markers analyzed among the 77 resistant and susceptible accessions generated 55 alleles, ranging from two to five, with an average of 3.43 alleles per locus. Principal coordinates analysis grouped the accessions on the basis of susceptibility and resistance to RKN infestation. The RKN-susceptible accessions exhibited higher variability as compared with resistant accessions, and they were more dispersed. Analysis of molecular variance showed maximum molecular variance was 78% within the population, and 22% between populations. Results of this study indicate that simple sequence repeat markers are reliable for assessing genetic variability among the RKN-resistant and RKN-susceptible mulberry accessions.

Isotope geochemistry reveals ontogeny of dispersal and exchange between main-river and tributary habitats in smallmouth bass Micropterus dolomieu.

Radiogenic strontium isotope ratios (87 Sr:86 Sr) in otoliths were compared with isotope ratios predicted from models and observed in water sampling to reconstruct the movement histories of smallmouth bass Micropterus dolomieu between main-river and adjacent tributary habitats. A mechanistic model incorporating isotope geochemistry, weathering processes and basin accumulation reasonably predicted observed river 87 Sr:86 Sr across the study area and provided the foundations for experimental design and inferring fish provenance. Exchange between rivers occurred frequently, with nearly half (48%) of the 209 individuals displaying changes in otolith 87 Sr:86 Sr reflecting movement between isotopically distinct rivers. The majority of between-river movements occurred in the first year and often within the first few months of life. Although more individuals were observed moving from the main river into tributaries, this pattern did not necessarily reflect asymmetry in exchange. Several individuals made multiple movements between rivers over their lifetimes; no patterns were found, however, that suggest seasonal or migratory movement. The main-river sport fishery is strongly supported by recruitment from tributary spawning, as 26% of stock size individuals in the main river were spawned in tributaries. The prevailing pattern of early juvenile dispersal documented in this study has not been observed previously for this species and suggests that the process of establishing seasonal home-range areas occurs up to 2 years earlier than originally hypothesized. Extensive exchange between rivers would have substantial implications for management of M. dolomieu populations in river-tributary networks.

Association of leaf micro-morphological characters with powdery mildew resistance in field-grown mulberry (Morus spp.) germplasm.

BACKGROUND AND AIMS: Micro-morphological characteristics can influence fungal infectivity. We sought links between micro-morphology and resistance to powdery mildew in mulberry with the intention of assisting selection of disease-resistant lines. METHODOLOGY: Over 3 years and under field conditions, we evaluated 30 lines of mulberry with contrasting susceptibilities to powdery mildew (15 resistant and 15 susceptible). Disease severity was related statistically to stomatal area, stomatal density, stomatal index, upper and lower cuticular thicknesses, leaf thickness and trichome density. PRINCIPAL RESULTS: Differences between lines were significant (P <0.05) for all characters studied. Variation between the resistant and susceptible groups was statistically highly significant (P <0.01) for stomatal index, stomatal area and trichome density. The powdery mildew-resistant group was distinguished by  17.4 % lower stomatal density, 12.5 % smaller stomatal index per unit leaf area, 20.0 % greater trichome density and 18.0 % higher stomatal area compared with the susceptible group. Trichome density was negatively correlated with disease severity index and with the accumulative area under disease progression curves. Stomatal density was positively correlated with both measures of disease severity. Although stomatal area was negatively related to disease severity index (r = -0.28; P <0.05), the correlation was weak. There was no statistically significant relationship between stomatal area and the accumulative area under disease progression curves. The germplasm was partitioned into seven sub-groups based on hierarchical cluster analysis derived from pooled disease severity index scores and three highly significant micro-morphological characters. Eighty per cent of the resistant germplasm accumulated in three cluster components (A1, A2 and B2) characterized by high trichome densities and a high stomatal density and stomatal index. CONCLUSIONS: Resistance to powdery mildew in mulberry is associated with trichome and stomatal features rather than leaf and epidermal thicknesses. Trichome density, stomatal density and stomatal index are shown to be promising markers for screening powdery mildew resistance in breeding programmes.

Drug-resistant tuberculosis in Egyptian children using Etest.

AIM: Etest (AB Biodisk, Solna, Sweden) is a new rapid and accurate alternative for susceptibility testing. It also can measure the minimal inhibitory concentration. The aim of this study was to assess the prevalence of drug-resistant Mycobacterium TB (MT) in newly diagnosed tuberculous Egyptian children, and to determine the effectiveness of the Etest to detect drug-resistant MT. METHODS: This prospective study included 150 newly diagnosed pulmonary and extrapulmonary tuberculous children. The organism was isolated and identified after decontamination. Antimicrobial susceptibility testing was performed by proportion method using Lowenstein-Jensen medium (PMLJ) and Etest. Minimal inhibitory concentration for both first and second line anti tuberculous drugs was determined by Etest. Comparison between the two methods was done. RESULTS: Age range was 6 months - 15 years (mean of 7.4+/-3.3). Pulmonary tuberculosis (TB) and extrapulmonary cases were 85/150 (55.3%) and 67/150 (44.7%) respectively. Seventy three isolates of MT were obtained from patients or contacts. Using Etest, the over all drug resistant of MT was 24.7% which is resistance to one drug (any drug). Resistance to first-line drugs; isoniazid, rifampicin, streptomycin and ethambutol was 5.4%, 2.7%, 6.8% and 1.4% respectively. Rifampicin resistance strongly correlated with isoniazid resistance. The prevalence of multi-drug resistance was 2.7%. Resistance to second line was 2.7% for amikacin and 1.4% for ciprofloxacin. Etest showed an overall specificity of 97.89 and sensitivity of 81.8. Overall agreement of Etest with reference proportion method range was 94.5-100%. CONCLUSION: Etest appears to be a good alternative method for testing susceptibility of Mycobacterium tuberculosis.

Synthesis and study of pigment aggregation response of some melatonin derivatives.

This study was performed to investigate the reactivity of melatonin towards various chemical reagents to produce new derivatives of melatonin containing extra- or fused heterocyclic systems such as the imidazoindole derivatives 3, 5, 6, the triazinoindole derivatives 8a, b, the thiadiazoloindole derivative 12, the pyridinoindole derivative 16 and the aminopyrazolomelatonin derivatives 21a, b and 22a, b. The structures of the compounds were established based on the analytical and spectral data. Agonist and antagonist potency of some melatonin derivatives in clonal Xenopus laevis melanophore cells was studied in comparison with melatonin.

The histomorphologic structure of the levator ani muscle and its functional significance.

The levator ani muscle (LAM), unlike other striated muscles has resting myoelectric activity, the cause of which is not precisely known. In a recent study this activity was suggested to be related to the presence of smooth muscle bundles in the LAM. The present study investigated this point in 25 cadaveric specimens (10 neonates, 15 adults). Histologic examination of the LAM was performed in 12 specimens, three to six slices being taken from the lateral to the medial side of each muscle, processed and stained with H&E and Masson's trichrome stain. The remaining 13 specimens were studied by direct dissection and photographed. Microscopic examination of specimens from adult cadavers showed that the lateral part of the LAM consisted of purely skeletal muscle bundles, mostly of the small-caliber type and few of the large or intermediate type. As we proceeded medially, smooth muscle bundles started to appear. Examination of slices medial to the midportion of the LAM showed that the muscle began to be separated into two layers: a deep (pelvic) one formed of smooth fibers and a superficial (perineal) one of skeletal fibers, separated by a neurovascular plane. Microscopic examination of specimens from neonates showed that the whole LAM consisted of skeletal fibers; no smooth fibers or separation into two layers were identified. By direct dissection of the adult specimens the medial part of the LAM consisted of two layers, superficial and deep, which were separated by fascia containing vessels and nerves. The muscle was thicker at its medial part and tapered laterally, with loss of demarcation, into two layers. Specimens from neonates showed no differentiation of the LAM, into two layers. It is suggested that the deep layer of the LAM, which was formed of smooth fibers, acts involuntarily, supporting the pelvic viscera by its tone and responding to variations in intra-abdominal pressure by adaptation of this tone. The superficial layer of the LAM, made of skeletal fibers, appears to represent the functional mobile part that acts voluntarily during urination or defecation. The presence of the smooth fibers in the adult LAM and not in neonates seems to be adaptational, caused by the action of intra.abdominal pressure and visceral weight. The skeletal fibers pass into various histologic stages before they transform to smooth fibers.

The reaction of digitoxin and digoxin with cyanoacetic acid hydrazide: synthesis of coumarin, thiazole, thiophene and pyridine derivatives with potential biological activities.

The reaction of either Digitoxin or Digoxin with cyanoacetic acid hydrazide gave the hydrazone derivatives 3a and 3b respectively. The reactivity of the latter products towards chemical reagents was studied to give heterocyclic derivatives with potential biological activities.

Transverse folds of rectum: anatomic study and clinical implications.

There are controversies with respect to the location, number, and function of the transverse folds of the rectum (TFR), probably because their physioanatomic aspects have not been fully investigated. The purpose of this communication was to study the anatomic and histologic structure of the TFR aiming at elucidation of their function in the light of their structure. The TFR were studied morphologically and histologically in 18 cadavers (10 male, 8 female) with a mean age of 36.6 +/- 10.4 (SD) years. Barium enema studies were also performed in 36 volunteers (20 male, 16 female; mean age 38.6 +/- 15.2 [SD] years). The number of TFR varied, the commonest findings being two and three. In a few cases, TFR were absent or exceeded three in number. Most folds extended beyond the middle of the rectal lumen; a few were narrow. They were thick at the base and tapered gradually. Microscopically, the TFR contained circular and longitudinal smooth muscle fibers; they were rarely purely mucosal. TFR varied in location dividing the rectum into compartments; an alternating side-to-side arrangement allows for a wavy movement of the stool in the rectum. The wavy movement, compartmental division, and the shelving action of the TFR are suggested to retard stool movement in the rectum so as to allow time for fecal sampling (stool or gas) and for impulses to reach the conscious level to decide whether or not to defecate. Further studies are needed to investigate the role of the TFR in clinical practice.

Sultamo-steroid analogues, Part VII: Synthesis of epi-androsterone derivatives with potential activity.

The reaction of epi-androsterone with cyanoacetyl hydrazine (2) gave the hydrazone derivative 3. The reactivity of 3 towards chemical reagents was studied to give pyridine, thiazole and thiophene derivatives.

Surgical anatomy of the somatic terminal innervation to the anal and urethral sphincters: role in anal and urethral surgery.

PURPOSE: The gross anatomy of the pudendal nerve branches was studied to identify more precisely the neuroanatomical relationship in the region of the anal canal, bladder neck and proximal urethra. Such knowledge is essential for the development of surgical techniques that avoid nerve injury in sphincteroplasty for anal and urinary stress incontinence, and in pudendal canal decompression. MATERIALS AND METHODS: The pudendal nerve terminal branches were dissected in 7 female and 5 male formalin fixed cadavers, including 6 fully mature neonates and 6 adults, a mean age of 37.6 years. The nerves were traced from the pudendal nerve to their termination in the anal and urethral sphincters, and pelvic floor muscles. RESULTS: The inferior rectal nerve occupied the lower half of the ischiorectal fossa. Immediately after emerging from the pudendal canal it extended a motor branch to the levator ani muscle and the cutaneous perianal and scrotal branches. The nerve terminated in the external anal sphincter at the 3 and 9 o'clock positions. Inside the pudendal canal the perineal nerve gave rise to a scrotal branch which joined the scrotal branch of the inferior rectal nerve to form the common scrotal nerve. About 2 to 3 cm. from the pudendal canal the perineal nerve extended a branch to the bulbocavernosus muscle and divided into the terminal scrotal and motor branches, which penetrated the striated urethral sphincter at the 3 and 9 o'clock positions. The deep dorsal nerve of penis or clitoris coursed forward into the ischiorectal fossa, emerged from the deep perineal pouch and penetrated the suspensory ligament to the dorsum of the penis or clitoris. CONCLUSIONS: The identification of the precise anatomical relation of the somatic nerve termination to the anal and urethral sphincters seems vital to avoid sphincter denervation during surgery for the correction of fecal and stress urinary incontinence.

Pudendal canal: surgical anatomy and clinical implications.

The anatomy of the pudendal canal (PC) was studied in 26 cadavers: 10 stillborn and 16 adults (mean age, 48.2 years). Two approaches were used to expose the PC: gluteal and perineal. The PC was an obliquely lying tube with a mean length of 0.8 cm in the stillborn and 1.6 cm in the adult cadavers. It started at a mean distance of 0.8 cm from the ischial spine in the stillborn and of 1.6 cm in the adult cadavers, and ended at a mean distance of 0.7 cm and 2.6 cm, respectively, from the lower border of the symphysis pubis. The PC wall was formed by the splitting of the obturator fascia and not by the lunate fascia. The PC contained the pudendal nerve and vessels embedded in loose areolar tissue. The three branches of the neurovascular bundle arose inside the canal in all but three cadavers. The wall of the PC consisted of collagen and elastic fibers, whereas that of the obturator fascia consisted of collagen only. The PC seems to be structurally adapted to serve certain functions. The criss-cross textile arrangement of collagen fibers in its wall allows the canal to change its shape in response to changes in pudendal vessels that occur during sexual activity. The elastic recoil may not only help to "pump" the blood up the pudendal vein, but also to prevent PC subluxation. The PC may, furthermore, act as a "pulley" for the neurovascular bundle. The pulley action may be disrupted by disordered pelvic floor muscles or defecation. Knowledge of the precise anatomy of the PC is necessary to carry out PC decompression in the treatment of PC syndrome.

Rectosigmoid junction: anatomical, histological, and radiological studies with special reference to a sphincteric function.

The existence of a sphincter at the rectosigmoid junction (RSJ) is controversial. Recent studies have demonstrated a high-pressure zone within the RSJ which responds to sigmoid colon or rectal contractions by relaxation or contraction, respectively. These findings suggest the presence of a "physiological" sphincter at the RSJ. The current study investigated the anatomical and histological structure and the radiological picture of the RSJ in view of the possible existence of an anatomical sphincter at the RSJ and elucidating its function. The RSJ was studied in 28 cadavers (18 adults and 10 fully mature neonates) by dissection. A histological study of the RSJ was performed in 5 cadavers. Radiological examination using double-contrast barium enema was carried out in 50 healthy volunteers (mean age 44.2+/-14.4 years; 32 men, 18 women). The mucous membrane of the RSJ was found in folds forming a "mucosal rosette" of a mean length of 2.8+/-0.9 cm in adult specimens and 0.7+/-0.2 cm in neonates. The distal end of the mucosal rosette was sharply delineated and in some specimens protruded into the rectal lumen as a small nipple, which was surrounded by a "rectal fornix" on either side. The histological examination of the RSJ showed mucosal foldings with deep crypts surrounded by lymphocytic aggregates and marginated by muscularis mucosa. The circular muscle coat showed gradually increasing thickness towards the rectum. Nerve cells in the submucosa were located at three levels: in the vicinity of the muscularis mucosa, in the middle of the submucosa, and in the proximity of the circular muscle. Radiologically the opening of the sigmoid colon into the RSJ presented as a ring or crescent. Radiological striations representing the mucosal rosette were demonstrated. The RSJ appeared as a narrow contractile segment. The anatomical, histological, and radiological findings thus indicate that the RSJ is a segment which can be identified by its interior rather than outer aspect. The study suggests the presence of an anatomical sphincter at the RSJ which seems to regulate the passage of stools from the sigmoid colon to the rectum.

Interaction of sub-inhibitory concentrations of ciprofloxacin and rifampicin against Staphylococcus aureus.

The frequency of the emergence of ciprofloxacin-resistant mutants to sub-inhibitory concentrations of ciprofloxacin, rifampicin, and ciprofloxacin plus rifampicin were compared in a subcutaneous abscess model of experimental Staphylococcus aureus infection in mice. The in vitro findings showed that the combination of ciprofloxacin and rifampicin was bacteriostatically additive for all strains tested when the combination was examined by the chequer-board technique and fractional inhibitory concentration indices determined. Animals were infected with ciprofloxacin-sensitive and ciprofloxacin-resistant test strains (6989S and 6989R) and left untreated for nine days, which showed that ciprofloxacin resistance had no effect on the pathogenicity of the organisms. In treated animals, ciprofloxacin plus rifampicin was found to be at least as effective as ciprofloxacin alone. However, in the murine model, the combination therapy produced significantly fewer high-level ciprofloxacin-resistant mutants than ciprofloxacin alone (p<0.0005). We conclude that a combination of ciprofloxacin and rifampicin was at least as efficient as either drug alone, and the additional presence of rifampicin reduced the emergence of high level ciprofloxacin-resistant sub-populations in the case of S. aureus subcutaneous abscesses in mice and so the combination may prove to be more efficient than ciprofloxacin alone.

In-vitro and in-vivo selection of Staphylococcus aureus mutants resistant to ciprofloxacin.

Staphylococcus aureus mutants resistant to ciprofloxacin were selected both in vitro and in vivo. In-vitro selection was achieved by incubating two strains of S. aureus (MICs of ciprofloxacin of 0.5 and 4 mg/L respectively) in the presence of ciprofloxacin in concentrations equivalent to 1/2 x MIC for 24 h and isolating the mutants on agar containing the quinolone at 1, 2 or 5 x MIC. Stably-resistant mutants of both strains were isolated, although the frequency of mutation of the susceptible strain was higher than that of the resistant strain. A murine subcutaneous abscess model was used for in-vivo selection. Mice which had been infected with a ciprofloxacin-susceptible strain of S. aureus were treated for 24 h with ciprofloxacin in a dosage which yielded concentrations in the abscess cavity equivalent to 1/2 or 1 x MIC for the pathogen. Additional groups of infected mice received ciprofloxacin for varying periods in a dosage which produced concentrations at the site of infection equivalent to 1/2 x MIC. Stably-resistant mutants were isolated from the abscesses, the number of mice from which mutants were isolated and the mutational frequency being inversely proportional to the dosage of ciprofloxacin administered and the duration of treatment. The results of this study confirm that, in the treatment of patients with infections caused by S. aureus, the dosage of ciprofloxacin should be adequate to ensure inhibitory concentrations at the site of infection.

Effect of sub-inhibitory concentrations of antibiotics on the virulence of Staphylococcus aureus.

The production of virulence factors by various bacteria can be influenced by sub-inhibitory concentrations of antibiotics. The effect of six antibiotics on the production of representative extracellular enzymes and toxins produced by Staphylococcus aureus was investigated. The production of the virulence determinants coagulase, protein A, alpha and delta haemolysin was monitored in the presence of ciprofloxacin, enoxacin, chloramphenicol, gentamicin, tetracycline and methicillin. The protein synthesis inhibitors reduced the production of coagulase and protein A, and almost completely inhibited the production of the haemolysins. Haemolysin production was also reduced by ciprofloxacin and enoxacin, but these antibiotics had little effect on the production of coagulase and protein A. Methicillin stimulated the production of alpha and delta haemolysins but had no effect on the production of coagulase and protein A.

[Investigation of caries occurrence and occlusal restoration in beginning school children in Erfurt compared to Marburg an der Lahn]. / Untersuching über Kariesbefall und Gebisssanierung bei Schulanfängern in Erfurt im Vergleich zu Marburg a.d. Lahn.

At the end of 1990 in the area of Erfurt 309 and in and around Marburg an der Lahn 348 school beginners were examined by one children's dentist under identical conditions. The results (milk teeth) showed that the caries incidence (dmfs) was comparable in both regions. However, the proportion of restored milk teeth tended to be higher in Erfurt than in Marburg. In addition, the differences in individual caries incidence were more marked. In Marburg there were more caries-free children, but children whose teeth had been damaged by caries were more seriously damaged than those in Erfurt.

Semen finger print.

A correlation between testosterone (T) and dihydrotestosterone (DHT) exists in seminal plasma. These androgens play a role in sperm maturation. The T/DHT ratio is different from one person to the other, due to the heterogenicity of seminal plasma which stems for the most part from the male accessory sex glands, the prostate and seminal vesicles, and also from the 'epididymo-testicular unit'. This ratio is useful in identifying the person's semen. Consequently, the steroid values from assailant semen or accused persons and semen on the victim's clothes are of cardinal importance in matching. The results reported include data on the validation of this technique as a tool for semen identification. Coital and masturbated semen were correlated, and consecutive coital semen were also analysed. It may be concluded that the T/DHT value is specific for each person.