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Herniorrhaphy with polypropylene mesh causing inguinal vasal obstruction: a preventable cause of obstructive azoospermia.

OBJECTIVE: To report a multiinstitutional experience of men presenting with infertility secondary to inguinal hernia repair using polypropylene mesh. SUMMARY BACKGROUND DATA: An estimated 80% of inguinal hernia operations involve placement of a knitted polypropylene mesh to form a "tension-free" herniorrhaphy. The prosthetic mesh induces a chronic foreign-body fibroblastic response creating scar tissue that imparts strength to the floor and leads to fewer recurrences. However, little is known about the long-term effects of the polypropylene mesh on the vas deferens, especially with regard to fertility. METHODS: Eight institutions in the United States reported a total of 14 cases of azoospermia secondary to inguinal vasal obstruction related to previous polypropylene mesh herniorrhaphy. Patient characteristics and operative findings were forwarded to 1 center for tabulation of data. RESULTS: Mean patient age was 35.5 years with an average duration of infertility of 1.8 years. Mean number of years between urologic evaluation and herniorrhaphy was 6.3 years. Types of inguinal hernia repair previously performed were: open (10), laparoscopic (2), or both (2). Nine patients had bilateral obstruction and 5 patients had unilateral obstruction with contralateral testicular atrophy or epididymal obstruction. Surgical exploration revealed a dense fibroblastic response encompassing the polypropylene mesh with either trapped or obliterated vas in all patients. Surgical reconstruction was performed in 8 of 14 men (57%). CONCLUSION: Reconstruction to restore fertility can be difficult secondary to fibrotic reaction. Before undergoing polypropylene mesh herniorrhaphy, men, especially of young reproductive age or with a solitary testicle, need to be carefully advised of potential obstruction and compromise to future fertility.

Adult↗

Sex causes altruism. Altruism causes sex. Maybe.

This study presents a mathematical model in which the fitness of an individual depends on the individual's genotype (individual effects) and on the genotypes of other members of the individual's local group (group effects). The findings suggest that, if phenotypes are a result of complex interactions between genes at different loci, then fitness-enhancing group effects may become common in sexual populations. The spread of fitness-enhancing group effects is facilitated when environmental conditions sometimes deteriorate temporarily. This is so even if the genotypes with the highest group effects also tend to have relatively low individual effects. In this sense, the process described here can lead to the evolution of altruism. By contrast, when populations are asexual it appears that group effects are much less important in determining the outcome of evolution. Thus, in nature, asexual populations may tend to be characterized by more antagonistic interactions than those that typically prevail when reproduction is sexual. This might help to explain why asexual lineages are prone to rapid extinction.

Altruism↗

Nephroptosis: a cause of renal pain and a potential cause of inaccurate split renal function determination.

We present 3 cases of nephroptosis encountered in young females over a 6-month period which posed diagnostic difficulties and gave inaccurate split renal function determinations until the true situation was disclosed. A syndrome is described of clinical presentation with right upper quadrant pain, erect hippuran renography showing an apparently small right kidney and reduced function but with normal time to peak and elimination phase on the curve (the "miniaturised" renogram) and erect and supine DMSA scintigraphy which confirms the diagnosis of abnormal renal mobility. Guidelines are suggested by which nephroptosis can be recognised and assessed in urological and nuclear medicine practice.

Adult↗

Sickle-cell trait in human biological and cultural evolution. Development of agriculture causing increased malaria is bound to gene-pool changes causing malaria reduction.

The particular agricultural adaptation we have been considering is the ultimate determinant of the presence of malaria parasites in the intracellular environment of the human red blood cell. This change in the cellular environment is deleterious for normal individuals, but individuals with the sickle-cell gene are capable of changing their red-cell environment so that intense parasitism never develops. Normal individuals suffer higher mortality rates and lower fertility rates in a malarious environment than individuals with the sickle-cell trait do, so the latter contribute proportionately more people to succeeding generations.

Africa, Eastern↗