bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of periapical radiographs in the recognition of C‐shaped mandibular second molars
Authors: Lambrianidis T. , Lyroudia K. , Pandelidou O. , Nicolaou A.
Published: March 2003

Aim

The purpose of this study was to evaluate in a blind trial the efficacy of radiographs to recognize C‐shaped mandibular second molars and to determine the incidence of this entity amongst second mandibular molars treated in the Department of Endodontology at the School of Dentistry of the University of Thessaloniki during a seven‐year period (1989–95).

Methodology

A total of 480 clinical records of root treated mandibular second molars were reviewed. The preoperative, working length, and final radiograph of each tooth alone and in combination were examined in groups as follows: group 1 (preoperative radiographs only), group 2 (working length radiographs), group 3 (final radiographs), group 4 (preoperative and working length radiographs), group 5 (preoperative and final radiographs) and group 6 (all three radiographs). The efficacy of each combination to identify the C‐shaped cases was evaluated based on the interpretation of three experienced dentists looking simultaneously at each case. Films were examined on a viewer using a magnifying glass and allowing a two‐week interval between groups. Results were compared with the clinical diagnoses stated on the patients’ records (group 7).

Results

The review of clinical records revealed that 4.58% of second molars had C‐shaped canals. Radiographic interpretation was overall more effective when based on film combinations (groups 4, 5, and 6) than on single radiographs. Amongst the latter, working length radiographs were more helpful than the preoperative and final ones. Preoperative radiographs were the least effective in diagnosing C‐shaped cases.

Conclusions

Simultaneous interpretation of preoperative, working length and post‐treatment radiographs is important when attempting to diagnose a C‐shaped configuration.
Influence of rotational speed, torque and operator proficiency on failure of Greater Taper files
Authors: Yared G. M. , Bou Dagher F. E. , Machtou P. , Kulkarni G. K.
Published: March 2003

Aim The purpose of this study was to evaluate the influence of rotational speed, torque, and operator experience on the incidence of locking, deformation, and separation of instruments when using a specific Ni–Ti rotary instrumentation technique in extracted human teeth.

Methodology Greater Taper Ni–Ti rotary instruments (GT) were used in a crown‐down technique. In one group (rotational speed evaluation) of canals (n = 300) speeds of 150, 250 and 350 r.p.m. (subgroups 1, 2 and 3) were used. Each one of the subgroups included 100 canals. In a second group (evaluation of torque) (n = 300) torque was set at 20, 30 and 55 Ncm (subgroups 4, 5 and 6). In the third group (evaluation of operator proficiency) (n = 300) three operators with varying experience (subgroups 7, 8 and 9) were also compared. Each subgroup included the use of 10 sets of GT rotary instruments and 100 canals of extracted human molars. Each set of instruments was used in up to 10 canals and sterilized before each case. NaOCl 2.5% was used as an irrigant. The number of locked, deformed, and separated instruments was recorded for each group. Statistical analysis was carried out with pairwise comparisons using Fisher’s exact tests for each of the failure type.

Results When the influence of rotational speed was evaluated, instrument deformation and separation did not occur in subgroups 1 (150 r.p.m.), 2 (250 r.p.m.), and 3 (350 r.p.m.). Instrument locking occurred in subgroup 3 only. Statistical analysis demonstrated a significant difference between the 150 and 350 r.p.m. groups and between the 250 and 350 r.p.m. groups with respect to instrument locking. In torque evaluation, neither separation, deformation nor locking occurred during the use of the instruments, at 150 r.p.m., and at the different torque values. When the operators were compared, although two instruments were separated in canals prepared by the least experienced operator, Fisher’s exact tests did not demonstrate a significant difference between the three subgroups. Instrument locking, deformation, and separation did not occur with the most experienced operator. None of the instruments separated with the trained operator.

Conclusions Preclinical training in the use of the GT rotary instruments when used with a crown‐down technique at 150 r.p.m. was crucial in avoiding instrument separation and reducing the incidence of instrument locking and deformation.
Root and canal morphology of Thai mandibular molars
Authors: Gulabivala K. , Opasanon A. , Ng Y.‐L. , Alavi A.
Published: March 2003

Aim To investigate the root and canal morphology of 351 mandibular permanent molars collected from an indigenous Thai population.

Methodology The cleaned teeth were accessed, the pulp dissolved by sodium hypochlorite under ultrasonication and the pulp system injected with Indian ink. The teeth were rendered clear by demineralization and immersion in methyl salicylate. The following observations were made: (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root; (iv) root canal configuration in each root using Vertucci’s classification, with additional modifications; and (v) presence and location of lateral canals and intercanal communications.

Results Of 118 mandibular first molars, 13% had a third disto‐lingual root. In three‐rooted teeth, 80% of the main distal roots and 100% of the disto‐lingual roots had type 1 canal systems. Of 60 mandibular second molars, 10% had C‐shaped roots, the majority of which had type I (33%) or type IV (33%) canal systems. Of 173 third molars, 68% had two separate roots, 20% had fused roots and 11% had a single C‐shaped root; the majority had two canals (61%).

Conclusions This study suggests that Thai molars exhibit features of both Caucasian and Chinese teeth.
Sperm characteristics and zona pellucida binding in relation to field fertility of frozen–thawed semen from dairy AI bulls
Authors: ZHANG  , LARSSON  , LUNDEHEIM  , RODRIGUEZ‐MARTINEZ
Published: March 2003

The present study examined the relationship between bull sperm characteristics immediately post‐thaw and some characteristics registered after swim‐up, including the ability of spermatozoa to bind to homologous zona pellucidae (ZP) in vitro, and fertility after artificial insemination (AI) of 9426 females. Frozen–thawed semen from 22 AI bulls of the Swedish Red and White Breed, represented by 43 different frozen batches (1–4 batches/bull, 2 consecutive ejaculates/batch), was examined with the aim of determining concentration, motility patterns, morphology and membrane integrity. In addition, the frozen–thawed spermatozoa were subjected to a swim‐up procedure and those separated in this way were tested with two assays of sperm‐binding to the ZP of homologous oocytes in vitro (ZBA), using either a relative ZBA index against a control bull of proven high fertility or absolute binding (Absolute ZBA). The correlations of the various sperm traits and 56‐day non‐return rates (NRR) after field AI were retrospectively examined as single traits and as combinations of traits (combined measures), including regression analysis of significant traits. Among the sperm characteristics, positively significant ( p < 0.01) correlations with NRR were found for linear motility post‐thawing (r = 0.45–0.59) and the concentration of motile spermatozoa after swim‐up (r = 0.43–0.63). Results obtained with the absolute ZBA approach were significantly ( p < 0.05) correlated with NRR (r = 0.50), whereas the correlation between NRR and the ZBA index was not significant. The use of combined measures of sperm traits, including the ability to bind to ZP, showed a stronger predictive correlation with NRR (r = 0.68–0.75), compared with single traits. The results suggest that the combined analysis of sperm linear‐motility patterns, swim‐up separated sperm motility and absolute ZBA can provide a valuable assessment of the fertilizing capacity of AI bull semen.
α‐Mannosidase from rat epididymal fluid is a ligand for phosphomannosyl receptors on the sperm surface
Authors: BELMONTE  , CHALLA  , GUTIERREZ  , BERTINI  , SOSA
Published: March 2003

This study demonstrates that α‐mannosidase from rat epididymal fluid is a ligand for phosphomannosyl receptors on the sperm surface. This enzyme was bound to intact epididymal spermatozoa with high affinity and in saturable form, and the binding was inhibited by mannose‐6‐phosphate but not by phosphorylated derivatives of fructose. Treatment of the enzyme with sodium periodate inhibited the binding of α‐mannosidase, confirming that a carbohydrate residue is involved in the interaction with spermatozoa. Evidence is also presented that the cation‐independent phosphomannosyl receptors are responsible for the interaction with α‐mannosidase. These findings suggest a new role for extracellular transport mediated by the mannose‐6‐phosphate receptor.
Influence of age and photoperiod on steroidogenic function of the testis in the golden hamster
Authors: Frungieri  , Gonzalez‐Calvar  , Bartke  , Calandra
Published: March 2003

The golden (Syrian) hamster is a seasonal breeder, and exposure of adult animals to short days results in severe gonadal regression with morphological features that resemble the immature testis. The purpose of this study was to investigate testicular steroidogenic capacity in the golden hamster and to analyse the influence of age and photoperiod on this process. Hamsters aged 36 days were maintained on a long photoperiod (14L:10D), and adult animals were then exposed to a long or a short photoperiod (6L:18D) for 14 weeks (the period of time required to achieve maximal gonadal regression), to assess circulating levels and in vitro production of testosterone, dihydrotestosterone and androstane‐3α,17β‐diol. In peripubertal hamsters, androstane‐3α,17β‐diol was the main circulating androgen detected, whereas in active adult animals, testosterone showed the highest serum levels. In hamsters exposed to a short photoperiod, blood testosterone levels were significantly lower than levels in adult hamsters exposed to a long photoperiod. Exposure of adult hamsters to a short photoperiod produced a marked reduction in serum concentrations of dihydrotestosterone and androstane‐3α,17β‐diol, which was not accompanied by a decrease in testicular 5α‐reductase activity. In the in vitro experiments, active adult testes were less sensitive than inactive adult testes to stimulation of androgen production with hCG, but showed similar sensitivity to the gonads from hamsters aged 36 days. In accordance with circulating androgen concentrations, the principal androgens produced in the in vitro assays from peripubertal and normal adult testes were androstane‐3α,17β‐diol and testosterone, respectively. Unexpectedly, the main androgen produced from regressed testes under in vitro conditions was androstane‐3α,17β‐diol. Inactive gonads released more androstane‐3α,17β‐diol than did normal adult testes and total in vitro androgen production (testosterone + dihydrotestosterone + androstane‐3α,17β‐diol) from adult testes was not diminished by exposure to a short photoperiod. However, in spite of the significant increase detected in production of androstane‐3α,17β‐diol in vitro from regressed testes, inactive gonads produced less androstane‐3α,17β‐diol than did peripubertal testes.  In summary, our studies suggest that testicular androgen biosynthetic capacity in adult hamsters exposed to short photoperiod is not reduced and these regressed testes represent an intermediate physiological state between peripubertal and active adult testes. The significant decrease detected in serum androgen concentrations during the involution phase could result from the absence of stimulating pituitary factors, together with a negative regulation of steroidogenesis by different non‐steroidal signals originating within and/or outside of the testis.
Semen banking in patients with cancer: 20‐year experience
Authors: Agarwa Ashok
Published: March 2003

Modern techniques of banking sperm provide an effective way to preserve the option of future fertility for most teenagers and young men diagnosed with a variety of malignancies that will necessitate treatment with chemotherapy, pelvic surgery, or significant radiation doses to the testes. Results of cumulative data collected at the Cleveland Clinic Foundation from patients with testicular cancer, lymphoma, leukemia, sarcoma, carcinoma and other kinds of malignancy have revealed that: (1) pretreatment semen quality (pre‐freeze and post‐thaw) in patients with cancer is poorer compared with healthy donors; (2) the percentage decline in semen quality (from pre‐freeze to post‐thaw) in patients with cancer is similar to that of normal donors. This suggested that the effect of cryodamage on spermatozoa from patients with cancer is similar to that of normal donors. (3) The stage of cancer in patients with testicular cancer and Hodgkin’s disease shows no relationship to their semen quality. Based on studies conducted at the Cleveland Clinic Foundation, we recommend that sperm cryopreservation be offered to all men of reproductive age who have malignancies. Cryopreservation is safe and inexpensive, and gives patients a chance to establish pregnancies in the future with an assisted reproductive technique.
Temporal control of protein synthesis during spermatogenesis
Authors: Braun Robert E.
Published: March 2003

During oogenesis and spermatogenesis transcription ceases prior to the differentiation of the mature cells. To complete germ cell differentiation and initiate early embryogenesis, proteins are synthesized from pre‐existing mRNAs that are stored for several days. It is well established that important regulatory elements functioning in spatial localization, temporal translation or messenger RNA stability are located in the 3′ untranslated region (3′ UTR) of mRNAs. During mammalian spermatogenesis temporal translational regulation of the protamine 1 (Prm1) mRNA is dependent on a highly conserved sequence located in the distal region of its 3′ UTR. The 17‐nucleotide translational control element (TCE) mediates translational repression of the Prm1 mRNA. Mutation of the TCE causes premature synthesis of protamine protein and sterility. The Prm1 mRNA is stored as a cytoplasmic ribonucleoprotein (mRNP) particle in spermatids. Contained within the particle are several members of the Y box family of nucleic acid binding proteins. In the yeast three‐hybrid system the murine Y box proteins MSY1, MSY2 and MSY4 bind in a sequence‐dependent manner to a conserved region in the proximal portion of the Prm1 3′ UTR. Sequence‐specific binding by MSY4 to the Y box recognition sequence (YRS) is dependent on the highly conserved cold shock domain, possibly through the RNP1 and RNP2 motifs present within it. The Y box proteins may function as translational repressors in vivo. Alternatively, their primary function may be to protect mRNAs from degradation during their extended period of storage. Translational activation of stored mRNAs is essential for the completion of gametogenesis. Proper translational activation of the Prm1 mRNA in elongated spermatids requires the cytoplasmic double‐stranded RNA binding protein TARBP2. Tarbp2 is expressed at low levels in many cells but is expressed at robust levels in late stage meiotic cells and in postmeiotic spermatids. Mice mutant for Tarbp2 are defective in proper translational activation of the Prm1 and Prm2 mRNAs and are sterile. Current studies are designed to determine the mechanism by which proteins bound to the 3′ UTR communicate with the 5′ end of the message to control translational silencing and activation.
Objective evaluation of the morphology of human epididymal sperm heads
Authors: Soler  , Pérez‐Sánchez  , Schulze  , Bergmann  , Oberpenning  , Yeung  , Cooper
Published: March 2003

Spermatozoa were obtained from nine epididymal regions of six epididymides taken from five men undergoing castration for prostatic carcinoma (53–76 years) and from one man with testicular cancer (38 years). Spermatozoa were obtained by mincing tissue in phosphate‐buffered saline, making air dried smears and staining with Hemacolor. The percentage of sperm heads categorised subjectively as normal (of uniform shape) or otherwise was calculated for each region. This confirmed that grossly swollen sperm heads (previously shown to be artefacts) were only present in proximal regions of the duct. A computer‐aided sperm morphology analyser (Sperm Class Analyzer®) was used to provide objective measurements of sperm head area, perimeter, length and width of the uniform sperm heads and revealed that there was a gradual and statistically significant decline in sperm head size upon maturation, as occurs in other species. There was no significant difference between the morphometric parameters of spermatozoa obtained from the distal cauda epididymis and those obtained from the ejaculates of young normozoospermic patients.
Expression of green fluorescent protein under beta‐actin promoter in living spermatogenic cells of the mouse: stage‐specific regulation by FSH
Authors: Ventelä Sami , Okabe Masaru , Tanaka Hiromitsu , Nishimune Yoshitake , Toppari Jorma , Parvinen Martti
Published: March 2003

Spermatogenic cells from a mouse strain expressing enhanced green fluorescent protein (EGFP) under chicken beta‐actin promoter were studied under living conditions to analyse stage‐ and cell‐specific expression and hormonal regulation of the transgene. The isolated seminiferous tubules were examined by transillumination and the live cell squashes by phase contrast and fluorescence microscopy. FSH effects were measured in whole seminiferous tubules comparing stages I–VI, VII–VIII and IX–XII of the cycle.

Beta‐actin was highly expressed in spermatogonia, but almost no expression was found at early meiosis (leptotene spermatocytes). A gradual increase in translation of beta‐actin was found during later stages of meiosis and early spermiogenesis, with a maximum in elongating spermatids. FSH increased the translation of beta‐actin after 4 h and 24 h of incubation at stages I–VI, after 24 h at stages VII–VIII but not at stages IX–XII of the cycle. The results support the view that beta‐actin plays a role in the nuclear elongation of spermatids and that its expression is regulated by FSH in a stage‐specific fashion. Techniques used in this study give us new insight to study temporal and hormonal regulation of gene products in living spermatogenic cells.
Effect of hyaluronan on monospermic penetration of porcine oocytes fertilized in vitro
Authors: Suzuki K. , Eriksson B. , Shimizu H. , Nagai T. , Rodriguez‐Martinez H.
Published: March 2003

An experimental series was carried out to examine the ability of exogenous hyaluronan (HA) to facilitate monospermic penetration of in vitro‐matured (IVM) oocytes during conventional porcine in vitro fertilization (IVF). IVM oocytes were co‐cultured in fertilization medium with frozen‐thawed, ejaculated boar spermatozoa. Addition of 0.5 mg/mL HA to the fertilization medium increased the rates of monospermic penetration (p < 0.05) on cumulus‐denuded oocytes, without detrimentally affecting penetration rates (rates of monospermy were 57% and 78% in 2 mM caffeine‐containing fertilization medium without and with HA, respectively). Caffeine and cumulus cells affected the rate of monospermic fertilization (p < 0.02–0.03), and caffeine affected the rate at which oocytes were penetrated (p < 0.02). Moreover, exogenous HA (0.5 mg/mL) in the sperm pre‐incubation medium promoted monospermic penetration rates without affecting overall penetration rates. The effects of exogenous HA on sperm penetration and monospermy were also compared among semen batches. After semen was pooled from three fertile boars and held in homologous seminal plasma (SP) for 3 (batch A), 10 (batch B) or 20 (batch C) h prior to being cooled, spermatozoa from each semen batch were co‐cultured with IVM oocytes. Monospermy of cumulus‐denuded oocytes was increased (p < 0.05) by the addition of exogenous HA within the same semen batch (batches B and C). Furthermore, co‐culture with cumulus cells did not mask the effects of HA on batch‐B semen. The concentration of exogenous HA (0, 0.05 and 0.5 mg/mL) during sperm–oocyte co‐culture differentially affected the rates of penetration and monospermy of cumulus‐intact oocytes, depending on the time spermatozoa were held in SP before being frozen. The highest penetration rate was obtained by exposing semen to SP for 20 h prior to being cooled (0.05 mg/mL HA). The results suggest that exogenous HA decreases polyspermy during conventional porcine IVF. Furthermore, it appears that the action of HA is dependent upon the priming action of seminal plasma.
Comparison between computerized slow‐stage and static liquid nitrogen vapour freezing methods with respect to the deleterious effect on chromatin and morphology of spermatozoa from fertile and subfertile men
Authors: Hammadeh M. E. , Dehn CH. , Hippach M. , Zeginiadou T. , Stieber M. , Georg T. , Rosenbaum P. , Schmidt W.
Published: March 2003

The purpose of this study was to determine the negative effects (cryodamage) on human spermatozoa after freeze‐thawing and to determine whether freeze‐thawing of spermatozoa with a programmed slow freezer is better than freezing with liquid nitrogen vapour (rapid freezing) with regard to alterations in sperm chromatin and morphology in semen from fertile (donor) and subfertile, IVF/ICSI, patients. Ninety‐five semen samples were obtained either from patients attending our IVF unit for treatment (n=34) or from donors (n=25) with proven fertility and normal sperm quality according to WHO guidelines. Each semen sample was divided into two parts after liquefaction and addition of the cryoprotectant. The first part was frozen using a programmed biological freezer and the second part was frozen by means of liquid nitrogen vapour. Smears were made before the freezing and after the thawing procedure to assess morphology (strict criteria) and chromatin condensation (Acridine Orange test). The mean percentage of chromatin condensed spermatozoa in the samples from donors (control group) was 92.4 ± 8.4% before freezing and this decreased significantly (p < 0.0001) to 88.7 ± 11.2% after freeze‐thawing with the computerized slow‐stage freezer and to 87.2 ± 12.3% after using static liquid nitrogen vapour (p < 0.001). The corresponding values for semen obtained from patients was 78.9 ± 10.3% before freezing which decreased to 70.7 ± 10.8 and 68.5 ± 14.8%, respectively (p < 0.001). On the other hand, the mean percentage of normal sperm morphology in the control group decreased from 26.3 ± 7.5% before freezing to 22.1 ± 6.4% (p < 0.0001) after thawing with the computerized slow‐stage freezer and to 22.2 ± 6.6% (p < 0.0001) after the use of static liquid nitrogen vapour. In the patient group, the mean percentage of normal morphology decreased from 11.7 ± 6.1% after freezing with the biological freezer to 9.3 ± 5.6% and to 8.0 ± 4.9% after freezing with static liquid nitrogen vapour.

This study demonstrates that chromatin packaging and morphology of human spermatozoa decrease significantly after the freeze‐thawing procedure, not only after the use of static liquid nitrogen vapour but also after the use of a computerized slow‐stage freezer. However, the chromatin of semen samples with normal semen parameters (donor sperm) withstand the freeze‐thaw injury better than those with low quality semen samples. Therefore, the computerized slow stage freezer could be recommended for freezing of human spermatozoa, especially for subnormal semen samples, for example, ICSI and ICSI/TESE candidates and from patients with testicular tumours or Hodgkin’s disease, in order to avoid further damage to the sperm chromatin structure.
Changes in binding of iodomelatonin to membranes of Leydig cells and steroidogenesis after prolonged in vitro exposure to melatonin
Authors: Valenti Sandra , Fazzuoli Laura , Giordano Giulio , Giusti Massimo
Published: March 2003

The aim of the present study was to investigate the effects of prolonged exposure to melatonin (MLT) on the binding of iodomelatonin to membranes of rat Leydig cells and the subsequent modulation of testosterone and cyclic adenocine monophosphate (cAMP) secretion from these cells by MLT itself. Leydig cells were Percoll‐purified from adult rats and cultured in vitro with MLT (1–100 nmol/L) for 16 h. Binding assays with 2(125I)iodomelatonin were then performed; moreover, testosterone and cAMP secretion during an acute challenge with lutenizing hormone (LH) (20 mIU/mL for 3 h) was assayed by RIA. As a result of prolonged MLT administration, a decrease in maximum binding density (Bmax) and equilibrium dissociation constant (Kd) of the binding of 2(125I)iodomelatonin to purified cell membranes was noted. Higher testosterone and cAMP secretion during LH challenge were recorded in cells pre‐incubated with MLT; notwithstanding, the inhibitory effect of acutely administered MLT on LH‐challenged secretions was not only retained but also reinforced, as the IC50 was 30% lower in cells pre‐treated with the higher concentration of MLT (100 n

M). Cycloheximide administration (10 μg/mL for 16 h) did not prevent hyper‐sensitization to LH challenge or to acute MLT administration on LH challenge. Pertussis toxin (180 ng/mL for 16 h) prevented hyper‐sensitization to LH, but not to acutely administered MLT. Forskolin (10 nmol/L) administration abolished either phenomena. In conclusion, prolonged exposure to MLT modulates the secretion of testosterone by cultured rat Leydig cells. Although MLT receptors were reduced, hyper‐sensitization to LH challenge and to acutely administered MLT on LH challenge were observed with the higher concentration of MLT. Reduction in intracellular cAMP as a result of prolonged administration of MLT, could be the primary cause of both phenomena. On the one hand, reduced cAMP could start re‐arrangement of the G‐proteins and thus LH‐dependent adenylate cyclase sensitization. On the other hand, reduced cAMP could render the Leydig cells more responsive to MLT itself through a mechanism which does not involve G‐protein re‐arrangement.
Varicocelectomy reduces reactive oxygen species levels and increases antioxidant activity of seminal plasma from infertile men with varicocele
Authors: Mostafa T. , Anis T. H. , El‐Nashar A. , Imam H. , Othman I. A.
Published: March 2003

Several theories have been advanced to explain the mechanisms by which varicocele impairs male fertility. These theories include scrotal hyperthermia, retrograde flow of adrenal or renal metabolites, Leydig cell dysfunction and hypoxia. Varicocele is reported to be associated with elevated reactive oxygen species (ROS) production in spermatozoa and diminished seminal plasma antioxidant activity. The aim of this study was to investigate whether surgical correction of varicocele might reduce ROS or increase the antioxidant capacity of seminal plasma from infertile patients with varicocele. The study group consisted of 68 infertile males, selected from patients scheduled for varicocelectomy at Cairo University Hospital during the year 1999. Seminal plasma levels of two ROS [malondialdehyde (MDA), hydrogen peroxide (H2O2)] and one ROS radical [nitric oxide (NO)] were estimated as well as six antioxidants [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), vitamin C (Vit C), vitamin E (Vit E), albumin) on the day prior to varicocelectomy. For comparison, the same parameters were measured again 3 and 6 months post‐operatively. A statistically significant reduction in the 3 month post‐operative levels of MDA, H2O2 and NO was observed when compared with the pre‐operative values. A further significant reduction took place during the following 3 months. Four of the six antioxidants tested (SOD, CAT, GPx, and Vit C) showed a significant increase in seminal levels when comparing 3‐month post‐operative with pre‐operative values. A further significant increase of the four antioxidant levels took place during the following 3 months. No significant change in the level of seminal plasma albumen took place during the first 3 months after varicocelectomy, however, a significant increase was noted during the next 3 months. In contrast to other antioxidants, seminal plasma levels of Vit E showed a significant decrease when comparing 3‐month post‐operative with pre‐operative values. A further significant decrease took place during the following 3 months. It is concluded that varicocelectomy reduces ROS levels and increases antioxidant activity of seminal plasma from infertile men with varicocele.
Penile pharmacotesting in diagnosing male erectile dysfunction: evidence for lack of accuracy and specificity
Authors: Aversa Antonio , Isidori Andrea M. , Caprio Massimiliano , Cerilli Marco , Frajese Vanni , Fabbri Andrea
Published: March 2003

Penile pharmacotesting (PPT) with alprostadil (PGE1) represents the most common diagnostic approach to male erectile dysfunction (ED). A positive response – i.e. normal erectile rigidity of sustained duration – is presumed to exclude venous or arterial pathology with enough accuracy. To test this assumption we compared PPT vs. flowmetric results obtained by colour‐duplex Doppler ultrasound (CDDU) in patients (pts) undergoing diagnostic evaluation for ED under conditions of maximal cavernous relaxation.

A total of 195 non‐consecutive impotent pts were diagnosed after dynamic CDDU as non‐vasculogenic (NOR), or having arteriogenic (AR), veno‐occlusive (VO) or mixed (MX) ED. Maximal erection obtained after PPT was scored as: type‐1 (full tumescence – no sustained rigidity, angle on the abdominal plane >90°), type‐2 (sustained partial erection, valid for intromission, angle=90°) and type‐3 (sustained full erection, angle <90°). Comparing PPT with flowmetric results, we found that a type‐3 response had 20% false negative diagnosis of NOR (17% of AR‐ and 3% of VO‐ and MX‐ED, respectively), while a type‐2 response had 63% false negative diagnosis (20% of AR, 37% of VO‐ and 6% MX‐ED, respectively). Type‐1 response was associated with the presence of VO dysfunction in 99% of cases.

These data suggest that a positive response to PPT (type‐2 and type‐3) assessed by the visual rating of erection is associated with both arterial (up to 20%) and/or VO (up to 43%) ED, as detected by CDDU. We conclude that PPT alone is a misleading diagnostic test to exclude vascular ED and that dynamic CDDU should be offered to pts investigated for male ED.
Sexological approach to ejaculatory dysfunction1
Authors: JANNINI E. A. , SIMONELLI C. , LENZI A.
Published: March 2003

Ejaculatory disorders include premature, deficient (delayed ejaculation and anejaculation) and retrograde ejaculation. A rare symptom connected to ejaculatory disorders is male anorgasmia. In the past, ejaculatory disorders were considered as typical relational and psychological symptoms. For this reason, a number of behavioural and psycho‐relational approaches have flourished from the first ideas of curing sexual problems with empirical therapy, focusing on the symptoms of sexual pathology. Such treatment includes assessment, behavioural and educational components, psychotherapy in the context of the relationship and sexual timetables. Recent advances in understanding the importance and frequency of ejaculatory disorders, insights into their organic and non‐organic pathophysiology and the efficacy of a growing arsenal of pharmacological therapies lead to a new challenge which can be confronted only with the development of new, integrated therapeutic alternatives from a modern somato‐psychic and holistic viewpoint.
Differential expression of succinyl CoA transferase (SCOT) genes in somatic and germline cells of the mouse testis
Authors: Tanaka H. , Iguchi N. , Miyagawa Y. , Koga M. , Kohroki J. , Nishimune Y.
Published: March 2003

Succinyl CoA:3‐oxo acid CoA transferase (SCOT/OXCT; EC 2.8.3.5) is a key mitochondrial enzyme in the metabolism of ketone bodies in various organs (but not in the liver). We identified a cDNA clone of the testicular germ cell‐specific succinyl CoA transferase isozyme (SCOT‐t). We then isolated a mouse orthologue of the SCOT/OXCT cDNA (SCOT‐s) and determined the expression of the two types of SCOT in the testis. The mRNAs of scot‐s and scot‐t were expressed exclusively in testicular somatic cells (i.e. Leydig and Sertoli cells) and germ cells, respectively. SCOT enzymatic activities were assayed in Leydig cell (SCOT‐s) and sperm (SCOT‐t) fractions. The SCOT activity in sperm was 2.5‐fold higher than that in Leydig cells. We conclude that germ cells and somatic cells differentially express the SCOT enzymes and that the SCOT activity of sperm caused exclusively by SCOT‐t should play an important role in sperm activity.
Immunopathology of in situ seminoma
Authors: Bols Birgitte , Jensen Leif , Jensen Anette , Brændstrup Otto
Published: March 2003

In this study of the seminomatous human testis the composition, activity and apoptosis of lymphocytes infiltrating the immune‐privileged seminiferous tubules with in situ seminoma were studied by immunohistochemistry and DNA fragmentation detection. Likewise the lymphocytes infiltrating the invasive seminomas were studied. The study showed equal numbers of CD4+ and CD8+ T cells and B cells, about 30% of the cells. Very few T γ/δ and NK cells were present. The activity in terms of IL‐2‐R, FasL and perforin expression was low. Apoptosis of the lymphocytic cells was limited. No differences were observed between the lymphocytes in seminiferous tubules with in situ seminoma and the lymphocytes in invasive tumours. The study suggests that either specifically committed lymphocytes are not present or, if present, immune‐suppressing mechanisms in addition to FasL may be working.
Biology of human papillomaviruses
Authors: Mcmurray H.R. , Nguyen D. , Westbrook T.F. , Mcance D.J.
Published: March 2003

Human papillomaviruses (HPVs) cause squamous cancers of epithelial surfaces, of which genital cancers are the most common. In this article we have attempted to describe the properties and functions of the viral proteins of HPV type 16, a common cause of genital cancers, and have tried to suggest how their expression may lead to a dysregulated cell which may become malignant. These viruses are attempting to replicate in terminally differentiating keratinocytes and must stimulate G1 to S‐phase progression for the replication of their genome. As part of the successful completion of replication and assembly of infectious virus particles, the virus needs at least partial differentiation to occur. Therefore, at the same time as differentiation is occurring, the nuclei of infected cells are in S‐phase. While the mechanisms of action of the viral proteins are not completely understood, researchers are making progress and this article strives to bring together the conclusions from some of this work.
Ultrastructure of Purkinje cell perikarya and their dendritic processes in the rat cerebellar cortex in experimental encephalopathy induced by chronic application of valproate
Authors: Sobaniec‐Lotowska Maria E.
Published: March 2003

Long‐term intragastric administration of the antiepileptic drug sodium valproate (Vuprol ‘Polfa’) to rats for 1, 3, 6, 9 and 12 months, once daily at the effective dose of 200 mg/kg body weight showed morphological evidence of encephalopathy, manifested by numerous nonspecific changes within Purkinje cell perikarya and their dendritic processes. The first ultrastructural abnormalities appeared after 3 months. They became more severe in animals with longer survival and were most pronounced after 12 months. The changes were maintained both 1 and 3 months after drug withdrawal. Mitochondria of Purkinje cell perikarya were most severely affected. Damage to mitochondria was accompanied by disintegration and fragmentation of granular endoplasmic reticulum, dilation of channels and cisterns of Golgi apparatus, enlargement of smooth endoplasmic reticulum elements including submembranous cisterns, and accumulation of profuse lipofuscin deposits. Frequently, Purkinje cells appeared as ‘dark’ ischemic neurones, with focally damaged cellular membrane and features of disintegration. Swollen Bergmann's astrocytes were seen among damaged Purkinje cells or at the site of their loss. The general pattern of submicroscopic alterations of Purkinje cell perikarya suggested severe disorders in several intercellular biochemical extents, including inhibition of oxidative phosphorylation and abnormal protein synthesis, both of which could lead to lethal damage. Ultrastructural abnormalities within dendrites were characterized by damage to elements of smooth endoplasmic reticulum, which was considerably enlarged, with formation of large vacuolar structures situated deep in the dendroplasm. Mitochondrial lesions and alterations in cytoskeletal elements – disintegration of microtubules or even their complete loss –were also observed. The general pattern of abnormalities within the organelles and cytoskeletal elements of dendritic processes in Purkinje cells in the VPA chronic experimental model imply that there are disturbances in detoxication processes. Furthermore these changes were irreversible, as they were maintained after drug withdrawal.
Effect of undernourishment on Herpes Simplex Virus Type 1 ocular infection in the Wistar rat model
Authors: BENENCIA FABIÁN , GAMBA GISELA , BENEDETTI RUBÉN , COURRÈGES MARÍA C. , CAVALIERI HERNÁN , MASSOUH ERNESTO J.
Published: March 2003

Abstract.  We have studied the susceptibility to Herpes Simplex Virus Type 1 (HSV‐1) infection in malnourished rats. Groups of 10 rats were undernourished during suckling by offspring duplication. The animals were put on commercial diet and at 1, 2, 3, 5 and 8 weeks after weaning, infected in the eye by scarification with HSV‐1, strain F. Significant differences in morbidity and mortality were observed between malnourished and control groups infected three weeks after weaning. Viral titres were higher in ocular washings and brains obtained from the malnourished group. This group showed a diminution in antigen dependent lymphocyte proliferation compared to control, and significantly lower delayed type hypersensitivity reaction against inactivated virus (malnourished = 0.16 ± 0.02 mm, control = 0.26 ± 0.03 mm, p < 0.05). Neutralizing antibodies in serum were lower in the malnourished group and lower levels of interferon were obtained in the malnourished group 24 h post‐infection. We conclude that malnutrition during suckling induces a delay in the capability to overcome HSV infection.
Dietary lectins can stimulate pancreatic growth in the rat
Authors: Kelsall Angela , FitzGerald A.J. , Howard C.V. , Evans R.C. , Singh R. , Rhodes J.M. , Goodlad R.A.
Published: March 2003

Lectins are proteins or glycoproteins of nonimmune origin, which bind specifically to carbohydrate structures. They are widespread in the human diet, and many are resistant to digestion. High doses of lectins have been shown to stimulate intestinal and pancreatic growth. The aim of the present study was to investigate the long‐term actions of low doses of lectins on the rat intestine and pancreas. A long‐term carcinogenesis study was performed using low levels (40 µg/rat/day) of peanut (PNA) or mushroom lectin (ABA) which bind to O‐linked (mucin‐type) oligosaccharides in the gut. While this was primarily designed as a colon carcinogenesis study, the pancreas was also investigated. No significant changes in colon carcinogenesis were seen, however, the colons were slightly heavier in the lectin treated groups. The weight of the pancreas was significantly greater (by 18 and 23%) in both lectin treated groups (P < 0.03/0.001). The weights of the acini and septal tissue were also increased by 39–46% in PNA and ABA fed animals, respectively (P < 0.002); there was no significant change in the endocrine pancreas.

In conclusion, long‐term feeding of low doses of lectin can influence pancreatic growth, and this trophic action may have potential adverse implications for the development of pancreatic cancer in humans.
Emulsifying properties of some legume proteins
Authors: Akintayo Emmanuel T. , Esuoso Kayode O. , Oshodi Aladesanmi A.
Published: March 2003

Protein concentrates of some Nigerian underused legume seed flours, lima bean (Phaseolus lunatus L.) and pigeon pea (Cajanus cajan), were prepared by alkaline extraction followed by acid precipitation, whereas that of African yam bean (Sphenotilis sternocarpa) was prepared by acid extraction followed by alkaline precipitation. Simple and objective means that allowed precise determination of the inversion point were used in investigating the capacity of the protein concentrates to emulsify fat. Their relative efficiencies as emulsion stabilizers were also investigated. The results revealed that the emulsifying capacities of these protein concentrates decreased with increasing protein concentration and emulsifying speed. However, emulsifying capacities increased with increasing initial aliquot size, whereas variation of speed of oil addition did not have any significant influence. The capacity of the protein concentrates to emulsify fat decreased in the order pigeon pea protein concentrate > lima bean protein concentrate > African yam bean protein concentrate. But for emulsion stability, the protein concentrates were in the opposite rank order.
Reduction in cholesterol and fractionation of butter oil using supercritical CO2 with adsorption on alumina
Authors: Mohamed Rahoma S. , Neves Guilherme B. M. , Kieckbusch Theo G.
Published: March 2003

Cholesterol reduction together with the fractionation of triglycerides in butter oil was obtained using a combined supercritical CO2 extraction/alumina adsorption process in a high‐pressure apparatus that allows the independent control of temperature and pressure. Cholesterol levels in butter oil fractions extracted at 40 °C and 27.6 MPa were reduced from 2.5 to 0.1 mg g−1 of oil. Butter oil was also fractionated into low‐, intermediate‐ or high‐molecular‐weight triglycerides. This single‐stage combined process is a clear indication of the important technological possibilities with a more efficient multistage fractionation followed by the subsequent blending and formation of desired milk fat products. A comparison of solubility data of pure cholesterol in CO2 with those for cholesterol contained in butter oil revealed the co‐solvency effects of triglycerides on the solvation of cholesterol.
Alicyclobacillus acidoterrestris in fruit juices and its control by nisin
Authors: Komitopoulou Evangelia , Boziaris Ioannis S. , Davies E. Alison , Delves‐Broughton Joss , Adams Martin R.
Published: March 2003

Summary The acid‐tolerant and heat‐resistant bacterium Alicyclobacillus acidoterrestris is a spoilage problem in pasteurized and heat‐treated fruit juices. In this study it was shown to grow in orange juice, grapefruit juice and apple juice to produce detectable taint at levels of about 104–105 c.f.u. ml−1. Decimal reduction times were determined at 80 °, 90 ° and 95 °C in each juice and confirmed the heat‐resistant nature of the spores under normal juice pasteurization conditions. They also confirmed that heat sensitivity increased with decreasing pH but that this effect was less pronounced at higher temperatures. The organism was, however, sensitive to the bacteriocin food preservative nisin. The presence of nisin during heating decreased the D value by up to 40% and the MIC for nisin against spores at 25 °C was only 5 International Units (IU) ml−1. The results indicate that use of nisin is a potentially useful way of controlling this organism in fruit juices and fruit juice‐containing products.
Effect of gelatin dip on the oxidative and colour stability of cooked ham and bacon pieces during frozen storage
Authors: Villegas R. , O'Connor T. P. , Kerry J. P. , Buckley D. J.
Published: March 2003

Summary Samples of cooked ham and bacon were dipped in water or 2, 4 or 6% gelatin solutions. Samples were then packed in oxygen permeable or vacuum packaging film and stored at −18 °C for seven months. Lipid oxidation (TBARS) and colour stability (Hunter a* values) were assessed monthly. The gelatin coating exerted beneficial effects on oxidative and colour stability.
Characteristic properties of equine milk proteins
Authors: Sugai Shintaro , Ikeguchi Masamichi , Shimizu Akio
Published: March 2003

Summary Properties of three equine milk proteins, lysozyme, α‐lactalbumin, and β‐lactoglobulin, were investigated and compared with the corresponding ones of bovine milk. The subsite structure similar to that in hen egg lysozyme was assumed in the functional region of lysozyme from interaction with inhibitors. α‐lactalbumin has structures similar to those of bovine, but less stability of its intact and 3SS forms are observed than the corresponding bovine irrespective of [Ca2+] because of the entropy factors. Although the folding of β‐lactoglobulin at acid pH is very similar to that of the bovine protein the conformation of the I strand is different from that of bovine I strand at neutral pH according to NMR data.
Evaluation of CIE‐lab colour parameters during the clarification of a sugar syrup from Mesquite pods (Prosopis Pallida L.)
Authors: Larrauri García José A. , Saura Calixto Fulgencio
Published: March 2003

SummaryThere are several commercial sugar syrups obtained from the Mesquite pods, however their dark‐brown colour limits their use in the food industry. In this work we clarified sugar syrups from Mesquite pods by a two‐step procedure: (1) lime‐milk treatment with the addition of different amounts of calcium hydroxide and aluminium sulphate, and (2) ion‐exchange treatment using A‐400 anionic and/or C‐100 cationic resins. Samples were evaluated for colour using the Hunter Lab colorimeter (Hunter Associates Laboratory Inc, Reston, VA, USA) (L*, a*, b*, ) and for sensory acceptability during the clarification process. The results showed that with the addition of 7.5% calcium hydroxide and 8.0% aluminium sulphate, followed by treatment with the anionic resin A‐400, a syrup with a high degree of purity (92.3%) and a lighter‐brown colour than other commercial samples could be obtained. The colour values, as measured by the Hunter meter were; a lightness of L* = 6.17 and a yellow colour of 0.74 expressed as a a/b* ratio. A negative correlation was obtained between the total polyphenol content (TP) in the sugar extract and the lightness values (L*); L* = 15.50–0.00511 TP (mg kg–1). The A‐400 resin retained the greatest amount of polyphenols (92.9%). CIE‐Lab parameters are proposed as a good means for objective colour comparison with other studies on the clarification of sugar syrups.
Temperature distribution analysis of a water cascading retort in rotary and static modes
Authors: Varga Szabolcs , Oliveira Jorge C. , Smout Chantal , Hendrickx Mark E.
Published: March 2003

Temperature distribution tests are normally performed to identify the coldest location in batch retorts in order to design safe processes. This work presents an approach to analysing temperature variability by considering its potential impact on lethality variability. The procedure is illustrated with the analysis of a four basket water cascading retort in both static and rotary modes, and is based on the numerical calculation of the F‐values from the experimental retort temperature histories, neglecting all other sources of variability. The temperature profiles were monitored basket by basket (thirty thermocouples in each basket, one at a time) and also in the whole retort (twenty thermocouples in four baskets). The location of the coldest point depended on whether only the heating phase or the complete cycle were considered. Replicates indicated that batch to batch variability can be a major factor.